cpu/x86/msr.h: Drop excessive includes

Change-Id: Ic22beaa47476d8c600e4081fc5ad7bc171e0f903
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/17735
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
diff --git a/src/include/cpu/amd/mtrr.h b/src/include/cpu/amd/mtrr.h
index be816ba..7da6cd1 100644
--- a/src/include/cpu/amd/mtrr.h
+++ b/src/include/cpu/amd/mtrr.h
@@ -37,6 +37,9 @@
 #define TOP_MEM_MASK_KB			(TOP_MEM_MASK >> 10)
 
 #if !defined(__PRE_RAM__) && !defined(__ASSEMBLER__)
+
+#include <cpu/x86/msr.h>
+
 void amd_setup_mtrrs(void);
 
 static inline __attribute__((always_inline)) msr_t rdmsr_amd(unsigned index)