README: add information for Debian packages

Add description for how to build Debian packages.

Signed-off-by: Damien Le Moal <[email protected]>

README.md

@@ -140,6 +140,19 @@ command.
 $ rpmbuild --rebuild libzbd-<version>.src.rpm
 ```
 
+### Building Debian Packages
+
+The procedure is similar to building RPM packages.
+
+```
+$ ./configure --enable-deb
+$ make deb
+```
+
+The above commands will build thre *.deb* packages: one binary package
+containing the libarary and example tools, a development package providing the
+library header files and a debug package.
+
 ## Library
 
 *libzbd* defines a set of functions and data structures simplifying the