[lldb] Added Debuginfod tests and fixed a couple issues

[kevinfrei]

Here we go with attempt number five. Again, no changes to the LLDB code diff, which has been reviewed several times.

For the tests, I added a @skipIfCurlSupportMissing annotation so that the Debuginfod mocked server stuff won't run, and I also disabled non-Linux/FreeBSD hosts altogether, as they fail for platform reasons on macOS and Windows. In addition, I updated the process for extracting the GNU BuildID to no create a target, per some feedback on the previous diff.

For reference, previous PR's (landed, backed out after the fact for various reasons) #90622, #87676, #86812, #85693

[kevinfrei]

FYI: The previous diff exposed a bug in some ARM code that @DavidSpicket fixed in #91585, but (for understandable reasons) he didn't want to be left holding the bag on restoring this diff, so I integrated some post-land feedback from @labath and put the diff back up for review.

[mysterymath]

This broke the Fuchsia CI builders' LLDB test suite:

https://luci-milo.appspot.com/ui/p/fuchsia/builders/toolchain.ci/clang-linux-x64/b8747217173107569041/overview

FAIL: LLDB (/b/s/w/ir/x/w/llvm_build/bin/clang-x86_64) :: test_normal_stripped_split_with_dwp (TestDebuginfodDWP.DebugInfodDWPTests.test_normal_stripped_split_with_dwp)
======================================================================
ERROR: test_debuginfod_both_okd_symfiles_from_service (TestDebuginfodDWP.DebugInfodDWPTests.test_debuginfod_both_okd_symfiles_from_service)
   Test behavior with both the only-keep-debug symbols and the dwp symbols
----------------------------------------------------------------------
Error when building test subject.

"/b/s/w/ir/x/w/llvm_build/bin/dwp" -o "a.out.dwp" main.dwo
/bin/sh: 1: /b/s/w/ir/x/w/llvm_build/bin/dwp: not found
make: *** [Makefile.rules:584: a.out.debug] Error 127
make: Leaving directory '/b/s/w/ir/x/w/llvm_build/lldb-test-build.noindex/debuginfod/SplitDWARF/TestDebuginfodDWP.test_debuginfod_both_okd_symfiles_from_service'

Test Directory:
/b/s/w/ir/x/w/llvm-llvm-project/lldb/test/API/debuginfod/SplitDWARF

======================================================================
ERROR: test_expr_dwarf (TestSharedLibStrippedSymbols.SharedLibStrippedTestCase.test_expr_dwarf)
   Test that types work when defined in a shared library and forwa/d-declared in the main executable
----------------------------------------------------------------------
Error when building test subject.


...

ifeq "" "YES"
/bin/sh: 1: ifeq: not found
make: *** [Makefile.rules:631: libfoo.so] Error 127
make: Leaving directory '/b/s/w/ir/x/w/llvm_build/lldb-test-build.noindex/lang/c/shared_lib_stripped_symbols/TestSharedLibStrippedSymbols.test_expr_dwarf'