MIPS/BFD: Handle branches in PLT compression selection

MIPS/BFD: Handle branches in PLT compression selection

Complement:

commit 1bbce132647e6d72aaa065cce5c1d5dd6585c2b2
Author: Maciej W. Rozycki <macro@linux-mips.org>
Date:   Mon Jun 24 23:55:46 2013 +0000

<https://sourceware.org/ml/binutils/2013-06/msg00077.html>, ("MIPS:
Compressed PLT/stubs support"), and also choose between regular and
compressed PLT entries as appropriate for any branches referring.

	bfd/
	* elfxx-mips.c (mips_elf_calculate_relocation): Handle branches
	in PLT compression selection.
	(_bfd_mips_elf_check_relocs): Likewise.

	ld/
	* testsuite/ld-mips-elf/compressed-plt-1.s: Add branch support.
	* testsuite/ld-mips-elf/compressed-plt-1a.s: Likewise.
	* testsuite/ld-mips-elf/compressed-plt-1b.s: Likewise.
	* testsuite/ld-mips-elf/compressed-plt-1-o32-branch.od: New
	test.
	* testsuite/ld-mips-elf/compressed-plt-1-o32-branch.rd: New
	test.
	* testsuite/ld-mips-elf/compressed-plt-1-o32-mips16-bronly.od:
	New test.
	* testsuite/ld-mips-elf/compressed-plt-1-o32-mips16-bronly.rd:
	New test.
	* testsuite/ld-mips-elf/compressed-plt-1-o32-mips16-branch.od:
	New test.
	* testsuite/ld-mips-elf/compressed-plt-1-o32-mips16-branch.rd:
	New test.
	* testsuite/ld-mips-elf/compressed-plt-1-o32-umips-bronly.od:
	New test.
	* testsuite/ld-mips-elf/compressed-plt-1-o32-umips-bronly.rd:
	New test.
	* testsuite/ld-mips-elf/compressed-plt-1-o32-umips-branch.od:
	New test.
	* testsuite/ld-mips-elf/compressed-plt-1-o32-umips-branch.rd:
	New test.
	* testsuite/ld-mips-elf/mips-elf.exp: Run the new tests.