[MIPS] When calculating a relocation using an undefined weak symbol don't check for overflow.

In MIPS the relocation calculation only ignores the overflow checks for undefined
weak symbols on relocations associated with j/jal.   This patch extends this to
the relocations used by the: b* instructions; pc/gp relative symbol offsets; and the
lwpc/ldpc MIPS r6 instructions.

bfd/
	* elfxx-mips.c (mips_elf_calculate_relocation): Only check for overflow
	on non-weak undefined symbols.

ld/testsuite/
	* ld-mips-elf/mips-elf.exp: Add in undefined weak overflow tests for
	o32, n32 and n64.
	* ld-mips-elf/undefweak-overflow.s: New test.
	* ld-mips-elf/undefweak-overflow.d: New test.
	* ld-mips-elf/undefweak-overflow-n32.d: New test.
	* ld-mips-elf/undefweak-overflow-n64.d: New test.
Add in a JALRC alias and fix the NAL instruction.

opcodes/

	* mips-opc.c (mips_builtin_opcodes): Add JALRC alias for JIALC.
	Remove the operand from NAL.

gas/testsuite/

	* gas/mips/r6.s: Test JALRC and NAL
	* gas/mips/r6-n32.d: Add expected output for JALRC and NAL.
	* gas/mips/r6-n64.d: Likewise.
	* gas/mips/r6.d: Likewise.
Fix undefined weak symbol reloc tests

ld/testsuite/

	* ld-mips-elf/mips-elf.exp: Update undefweak-overflow tests.
	* ld-mips-elf/undefweak-overflow-n32.d: Remove.
	* ld-mips-elf/undefweak-overflow-n64.d: Likewise.
	* ld-mips-elf/undefweak-overflow.s: Set mips64r6, noreorder and
	add a label to mark the micromips region.
	* ld-mips-elf/undefweak-overflow.d: Update expected output.
Fix all failing FPXX tests for tx39-elf.

ld/testsuite/

	* ld-mips-elf/attr-gnu-4-00.d: Relax check for ISA extension.
	* ld-mips-elf/attr-gnu-4-01.d: Likewise.
	* ld-mips-elf/attr-gnu-4-02.d: Likewise.
	* ld-mips-elf/attr-gnu-4-03.d: Likewise.
	* ld-mips-elf/attr-gnu-4-08.d: Likewise.
	* ld-mips-elf/attr-gnu-4-10.d: Likewise.
	* ld-mips-elf/attr-gnu-4-11.d: Likewise.
	* ld-mips-elf/attr-gnu-4-18.d: Likewise.
	* ld-mips-elf/attr-gnu-4-20.d: Likewise.
	* ld-mips-elf/attr-gnu-4-22.d: Likewise.
	* ld-mips-elf/attr-gnu-4-28.d: Likewise.
	* ld-mips-elf/attr-gnu-4-30.d: Likewise.
	* ld-mips-elf/attr-gnu-4-33.d: Likewise.
	* ld-mips-elf/attr-gnu-4-38.d: Likewise.
	* ld-mips-elf/attr-gnu-4-44.d: Likewise.
Rework the alignment check for BFD_RELOC_MIPS_18_PCREL_S3.

gas/

	* config/tc-mips.c (md_apply_fix): Apply alignment check
	to the symbol and offset rather than *valP for
	BFD_RELOC_MIPS_18_PCREL_S3.  Also update the error message
	for BFD_RELOC_MIPS_19_PCREL_S2.

gas/testsuite/

	* gas/mips/r6-64.s: Remove .align directives from LDPC
	instructions and add further tests for LDPC.
	* gas/mips/r6-64-n32.d: remove the NOPs from LDPC expected
	output and update for new tests.
	* gas/mips/r6-64-n64.d: Likewise.
	* gas/mips/ldpc-unalign.l: New file.
	* gas/mips/ldpc-unalign.s: Likewise.
	* gas/mips/mips.exp: Run ldpc-unalign test.
Automatic date update in version.in