[BFD][AARCH64]Add TLSGD relaxation support under large memory model.

[BFD][AARCH64]Add TLSGD relaxation support under large memory model.

bfd/

2015-10-02  Renlin Li <renlin.li@arm.com>

	* elfnn-aarch64.c(IS_AARCH64_TLS_RELAX_RELOC):
	Add relaxation support for TLSGD_MOVW_G0_NC and TLSGD_MOVW_G1.
	(aarch64_tls_transition_without_check): Likewise
	(elfNN_aarch64_tls_relax): Likwise.

ld/testsuite/

2015-10-02  Renlin Li <renlin.li@arm.com>

	* ld-aarch64/aarch64-elf.exp: run new test
	* ld-aarch64/tls-relax-large-gd-ie.d: New.
	* ld-aarch64/tls-relax-large-gd-ie.s: New.
	* ld-aarch64/tls-relax-large-gd-le.d: New.
	* ld-aarch64/tls-relax-large-gd-le.s: New.