* target-reloc.h (relocate_section): Check whether a symbol is

	* target-reloc.h (relocate_section): Check whether a symbol is
	defined by the ABI before reporting an undefined symbol error.
	* target.h (Target::is_defined_by_abi): Make parameter const.
	(Target::do_is_defined_by_abi): Likewise.
	* i386.cc (Target_i386::do_is_defined_by_abi): Likewise.
	* powerpc.cc (Target_powerpc::do_is_defined_by_abi): Likewise.
	* sparc.cc (Target_sparc::do_is_defined_by_abi): Likewise.
	* x86_64.cc (Target_x86_64::do_is_defined_by_abi): Likewise.
	* testsuite/Makefile.am (tls_test_shared.so): Add -Wl,-z,defs.
	* testsuite/Makefile.in: Rebuild.