Set BFD_DECOMPRESS when reading build-id debuglink

Set BFD_DECOMPRESS when reading build-id debuglink

We should set BFD_DECOMPRESS to decompress sections unless dumping the
section contents when reading build-id debuglink.

	PR binutils/31925
	* objdump.c (open_debug_file): Set BFD_DECOMPRESS to decompress
	sections unless dumping the section contents.
	* testsuite/binutils-all/objdump.exp (test_build_id_debuglink):
	Add a compress option.
	Run test_build_id_debuglink with none and zlib.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>