[PR22764][LD][AARCH64]Allow R_AARCH64_ABS16 and R_AARCH64_ABS32 against absolution...

[PR22764][LD][AARCH64]Allow R_AARCH64_ABS16 and R_AARCH64_ABS32 against absolution symbol or undefine symbol in shared object.

The assumption that R_AARCH64_ABS16 and R_AARCH64_ABS32 relocation in LP64 abi
will be used to generate an address does not hold for absolute symbol.
In this case, it is a value fixed at static linking time.

The condition to check the relocations is relax to allow absolute symbol and
undefined symbol case.

bfd/

2018-02-05  Renlin Li  <renlin.li@arm.com>

	PR ld/22764
	* elfnn-aarch64.c (elfNN_aarch64_check_relocs): Relax the
	R_AARCH64_ABS32 and R_AARCH64_ABS16 for absolute symbol. Apply the
	check for writeable section as well.

ld/

2018-02-05  Renlin Li  <renlin.li@arm.com>

	PR ld/22764
	* testsuite/ld-aarch64/emit-relocs-258.s: Define symbol as an address.
	* testsuite/ld-aarch64/emit-relocs-259.s: Likewise.
	* testsuite/ld-aarch64/aarch64-elf.exp: Run new test.
	* testsuite/ld-aarch64/pr22764.s: New.
	* testsuite/ld-aarch64/pr22764.d: New.