x86, cpu, amd: Fix a shadowed variable situation

Having u32 and struct cpuinfo_x86 * by the same name is not very smart,
although it was ok in this case due to the limited scope of u32 c and it
being used only once in there.

Fix this.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1389786735-16751-1-git-send-email-bp@alien8.de


Signed-off-by: H. Peter Anvin <hpa@zytor.com>