Add PIC and TLS support to the ARC target.

Add PIC and TLS support to the ARC target.

bfd/ChangeLog:
	* arc-plt.def: New file.
	* arc-plt.h: Likewise.
	* elf32-arc.c (elf_arc_abs_plt0_entry, elf_arc_abs_pltn_entry,
		       elf_arcV2_abs_plt0_entry, elf_arcV2_abs_pltn_entry,
		       elf_arc_pic_plt0_entry, elf_arc_pic_pltn_entry,
		       elf_arcV2_pic_plt0_entry, elf_arcV2_pic_pltn_entry): Remove.
	(name_for_global_symbol): Added.
	(ADD_RELA): Helper to create dynamic relocs.
	(new_got_entry_to_list): Create a new got entry in linked list.
	(symbol_has_entry_of_type): Search for specific type of entry in
	list.
	(is_reloc_for_GOT): return FALSE for any TLS related relocs.
	(is_reloc_for_TLS, arc_elf_set_private_flags)
	(arc_elf_print_private_bfd_data, arc_elf_copy_private_bfd_data)
	(arc_elf_merge_private_bfd_data): New functions.
	(debug_arc_reloc): Cleaned debug info printing.
	(PDATA reloc): Changed not to perform address alignment.
	(reverse_me): Added. Fix for ARC_32 relocs.
	(arc_do_relocation): Return bfd_reloc_of when no relocation should
	occur.
	(arc_get_local_got_ents): Renamed from arc_get_local_got_offsets.
	Changed function to access an array of list of GOT entries instead
	of just an array of offsets.
	(elf_arc_relocate_section): Added support for PIC and TLS related relocations.
	(elf_arc_check_relocs): Likewise.
	(elf_arc_adjust_dynamic_symbol, elf_arc_finish_dynamic_symbol,
	(elf_arc_finish_dynamic_sections): Likewise
	(arc_create_dynamic_sections): Modified conditions to create
	dynamic sections.
	(ADD_SYMBOL_REF_SEC_AND_RELOC): New macro.
	(plt_do_relocs_for_symbol, relocate_plt_for_symbol)
	(relocate_plt_for_entry): Changed to support new way to define PLT
	related code.
	(add_symbol_to_plt): Likewise.
	(arc_elf_link_hash_table_create): New function.

include/ChangeLog:
	* elf/arc-reloc.def (ARC_32, ARC_GOTPC, ARC_TLS_GD_GOT)
	(ARC_TLS_IE_GOT, ARC_TLS_DTPOFF, ARC_TLS_DTPOFF_S9, ARC_TLS_LE_S9)
	(ARC_TLS_LE_32): Fixed formula.
	(ARC_TLS_GD_LD): Use new special function.
	* opcode/arc-func.h: Changed all the replacement
	functions to clear the patching bits before doing an or it with the value
	argument.