[PATCH, AArch64] Improve relocation error check in elf64_aarch64_check_relocs.

[nick clifton]

Hi Will,

> bfd/ChangeLog:
>
> 2013-04-26  Will Newton<will.newton@linaro.org>
>
> 	* elf64-aarch64.c (elf64_aarch64_check_relocs): Move relocation
> 	error check up and add error message.

Approved and applied.

Cheers
   Nick