arch/x86/cpu.c: Remove unneeded headers

Change-Id: I35fcf25906bf7fe5af133618654bb121404743fc
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/26025Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

src/arch/x86/cpu.c

@@ -18,8 +18,6 @@
 #include <arch/io.h>
 #include <string.h>
 #include <cpu/x86/mp.h>
-#include <cpu/x86/mtrr.h>
-#include <cpu/x86/msr.h>
 #include <cpu/x86/lapic.h>
 #include <cpu/x86/tsc.h>
 #include <arch/cpu.h>