[PATCH] Expand mempcpy into memcpy

[David Miller]

From: Ondřej Bílka <neleai@seznam.cz>
Date: Wed, 6 Feb 2013 21:38:48 +0100

> Perhaps best way is use my header as default and architectures with optimized
> mempcpy need to enable it with _HAVE_STRING_ARCH_mempcpy.

I personally would rather have the default be the other way around,
this is a non-intuitive thing to have to "discover" that you have
to do when you optimize mempcpy properly.