Extend --compress-debug-sections in gold

Extend --compress-debug-sections in gold

This patch extends --compress-debug-sections= with [zlib-gnu|zlib-gabi]
in gold.

	PR gold/18322
	* compressed_output.cc (zlib_compress): Add argument for
	compression header size.  Set header size to compression header
	size if it isn't 0.  Don't write out the zlib header here.
	(Output_compressed_section::set_final_data_size): Support
	zlib-gnu and zlib-gabi compressions.  Pass compression header
	size to zlib_compress and write out compression header.  Set
	the SHF_COMPRESSED bit for zlib-gabi compression.  Otherwise
	clear the SHF_COMPRESSED bit
	* options.h (compress_debug_sections): Add zlib-gnu and
	zlib-gabi.
	* output.h (Output_section::set_flags): New.
	* testsuite/Makefile.am (check_PROGRAMS): Add
	flagstest_compress_debug_sections_none,
	flagstest_compress_debug_sections_gnu and
	flagstest_compress_debug_sections_gabi.
	(check_DATA): Add flagstest_compress_debug_sections_none.stdout.
	flagstest_compress_debug_sections.stdout,
	flagstest_compress_debug_sections.cmp,
	flagstest_compress_debug_sections.check,
	flagstest_compress_debug_sections_gnu.stdout,
	flagstest_compress_debug_sections_gnu.cmp,
	flagstest_compress_debug_sections_gnu.check,
	flagstest_compress_debug_sections_gabi.stdout,
	flagstest_compress_debug_sections_gabi.cmp and
	flagstest_compress_debug_sections_gabi.check.
	(flagstest_compress_debug_sections_none): New.
	(flagstest_compress_debug_sections_none.stdout): Likewise.
	(flagstest_compress_debug_sections.stdout): Likewise.
	(flagstest_compress_debug_sections.check): Likewise.
	(flagstest_compress_debug_sections.cmp): Likewise.
	(flagstest_compress_debug_sections_gnu): Likewise.
	(flagstest_compress_debug_sections_gnu.stdout): Likewise.
	(flagstest_compress_debug_sections_gnu.check): Likewise.
	(flagstest_compress_debug_sections_gnu.cmp): Likewise.
	(flagstest_compress_debug_sections_gabi): Likewise.
	(flagstest_compress_debug_sections_gabi.stdout): Likewise.
	(flagstest_compress_debug_sections_gnu.check): Likewise.
	(flagstest_compress_debug_sections_gnu.cmp): Likewise.
	* testsuite/Makefile.in: Regenerated.