[patch, mips] Fix memcpy for mipsisa64-elf target

[Jeff Johnston]

On 01/07/2013 12:30 PM, Steve Ellcey wrote:
> 2013-01-07  Steve Ellcey<sellcey@mips.com>
>
> 	* libc/machine/mips/memcpy.S (memcpy): Check if _MIPS_SIM is set.
>

Patch checked in, thanks.  In the future, please attach your patches to 
such posts as it makes it easier to apply the patches.

-- Jeff J.