PowerPC64 __tls_get_addr sequence optimization

There isn't a good reason for ld.bfd to behave differently from gold
in the code generated by TLS GD/LD to LE optimization.

bfd/
	* elf64-ppc.c (ppc64_elf_relocate_section): When optimizing
	__tls_get_addr call sequences to LE, don't move the addi down
	to the nop.  Replace the bl with addi and leave the nop alone.
ld/
	* testsuite/ld-powerpc/tls.d: Update.
	* testsuite/ld-powerpc/tlsexe.d: Update.
	* testsuite/ld-powerpc/tlsexetoc.d: Update.
	* testsuite/ld-powerpc/tlsld.d: Update.
	* testsuite/ld-powerpc/tlsmark.d: Update.
	* testsuite/ld-powerpc/tlsopt4.d: Update.
	* testsuite/ld-powerpc/tlstoc.d: Update.