This patch adds support for ARM PLT entries that support a full 32-bit offset range.

This patch adds support for ARM PLT entries that support a full 32-bit offset range.
Enabled via the use of a new linker command line option: --long-plt.

	* bfd-in.h: Add export of bfd_elf32_arm_use_long_plt.
	* bfd-in2.h: Regenerate.
	* elf32-arm.c (elf32_arm_plt_entry_long): New array.
	(elf32_arm_link_hash_table_create): Set plt_entry_size to 16 if
	using long PLT entries.
	(bfd_elf32_arm_use_long_plt): New function.
	(elf32_arm_populate_plt_entry): Add support for long PLT entries.

	* emultempl/armelf.em (OPTION_LONG_PLT): Define.
	(PARSE_AND_LIST_LONGOPTS): Add long-plt.
	(PARSE_AND_LIST_OPTIONS): Likewise.
	(PARSE_AND_LIST_ARGS_CASES): Handle long-plt.
	* ld.texinfo: Document --long-plt.

	* ld-arm/long-plt-format.s: New test case.
	* ld-arm/long-plt-format.d: Expected disassembly.
	* ld-arm/arm-elf.exp: Run the new test.