gold: Add support for sparc GOTDATA optimizations in Gold.

gold: Add support for sparc GOTDATA optimizations in Gold.

gold/

	* sparc.cc (Target_sparc::got_address): New function.
	(Sparc_relocate_functions::gdop_hix22): New function.
	(Sparc_relocate_functions::gdop_lox10): New function.
	(Target_sparc::Scan::local): Do not emit a GOT entry for GOTDATA
	relocs.
	(Target_sparc::Scan::local): Likewise if the global symbol is not
	preemptible and is not IFUNC.
	(Target_sparc::Relocate::relocate): Perform GOTDATA code
	transformations for local and non-preemptible non-IFUNC global
	symbols.