Added documentation for Intel GPU support and setcap command to Makefile

Makefile

@@ -283,6 +283,7 @@ help:
 	@printf "  clean        Remove built objects\n"
 	@printf "  distclean    Remove built objects and binaries\n"
 	@printf "  install      Install btop++ to \$$PREFIX ($(PREFIX))\n"
+	@printf "  setcap       Set extended capabilities on binary (preferable to setuid)\n"
 	@printf "  setuid       Set installed binary owner/group to \$$SU_USER/\$$SU_GROUP ($(SU_USER)/$(SU_GROUP)) and set SUID bit\n"
 	@printf "  uninstall    Uninstall btop++ from \$$PREFIX\n"
 	@printf "  info         Display information about Environment,compiler and linker flags\n"
@@ -355,6 +356,12 @@ setuid:
 	@printf "\033[1;92mSetting SUID bit\033[0m\n"
 	@chmod u+s $(DESTDIR)$(PREFIX)/bin/btop
 
+#? Run setcap on btop for extended capabilities
+setcap:
+	@printf "\033[1;97mFile: $(DESTDIR)$(PREFIX)/bin/btop\n"
+	@printf "\033[1;92mSetting capabilities...\033[0m\n"
+	@setcap cap_perfmon=+ep $(DESTDIR)$(PREFIX)/bin/btop
+
 # With 'rm -v' user will see what files (if any) got removed
 uninstall:
 	@printf "\033[1;91mRemoving: \033[1;97m$(DESTDIR)$(PREFIX)/bin/btop\033[0m\n"

README.md

@@ -225,7 +225,7 @@ Also needs a UTF8 locale and a font that covers:
 * Unicode Block “Geometric Shapes” U+25A0 - U+25FF
 * Unicode Block "Box Drawing" and "Block Elements" U+2500 - U+259F
 
-### **Optional Dependencies (Needed for GPU monitoring)**
+### **Optional Dependencies (Needed for GPU monitoring) (Only Linux)**
 
 GPU monitoring also requires a btop binary built with GPU support (`GPU_SUPPORT=true` flag).
 
@@ -241,6 +241,14 @@ In addition to that you must also have the nvidia-ml dynamic library installed,
 
 If you have an AMD GPU `rocm_smi_lib` is required, which may or may not be packaged for your distribution.
 
+ * **INTEL**
+
+Requires a working C compiler if compiling from source - tested with GCC12 and Clang16.
+
+Also requires the user to have permission to read from SYSFS.
+
+Can be set with `make setcap` (preferred) or `make setuid` or by running btop with `sudo` or equivalent.
+
 ### **Notice (Text rendering issues)**
 
 * If you are having problems with the characters in the graphs not looking like they do in the screenshots, it's likely a problem with your systems configured fallback font not having support for braille characters.
@@ -299,11 +307,19 @@ If you have an AMD GPU `rocm_smi_lib` is required, which may or may not be packa
    sudo make install
    ```
 
-3. **(Optional) Set suid bit to make btop always run as root (or other user)**
+3. **(Optional/Required for Intel GPU) Set extended capabilities or suid bit to btop**
 
    Enables signal sending to any process without starting with `sudo` and can prevent /proc read permissions problems on some systems.
 
-   * **Run setuid.sh or:**
+   Is required for Intel GPU support.
+
+   * **Run:**
+
+   ```bash
+   # run after make install and use same PREFIX if any was used at install
+   sudo make setcap
+   ```
+   * **or**
 
    ```bash
    # run after make install and use same PREFIX if any was used at install
@@ -367,11 +383,9 @@ If you have an AMD GPU `rocm_smi_lib` is required, which may or may not be packa
 
    ### GPU compatibility
 
-   Btop++ supports NVIDIA and AMD GPUs out of the box on Linux x86_64, provided you have the correct drivers and libraries.
+   Btop++ supports Nvidia and AMD GPUs and Intel IGPUs out of the box on Linux x86_64, provided you have the correct drivers and libraries.
 
-   Compatibility with Intel GPUs using generic DRM calls is planned, as is compatibility for FreeBSD and macOS.
-
-   Gpu support will not work when static linking glibc (or musl, etc.)!
+   Gpu support for Nvidia or AMD will not work when static linking glibc (or musl, etc.)!
 
    For x86_64 Linux the flag `GPU_SUPPORT` is automatically set to `true`, to manually disable gpu support set the flag to false, like:
 
@@ -448,18 +462,26 @@ If you have an AMD GPU `rocm_smi_lib` is required, which may or may not be packa
 
    Notice! Only use "sudo" when installing to a NON user owned directory.
 
-5. **(Optional) Set suid bit to make btop always run as root (or other user)**
-
-   ```bash
-   sudo make setuid
-   ```
+5. **(Optional/Required for Intel GPU support) Set extended capabilities or suid bit to btop**
 
    No need for `sudo` to enable signal sending to any process and to prevent /proc read permissions problems on some systems.
 
+   Also required for Intel GPU monitoring.
+
    Run after make install and use same PREFIX if any was used at install.
 
+   ```bash
+   sudo make setcap
+   ```
+
+   or
+
    Set `SU_USER` and `SU_GROUP` to select user and group, default is `root` and `root`
 
+   ```bash
+   sudo make setuid
+   ```
+
 * **Uninstall**
 
    ```bash