x86, mce: fix typo in comment in asm/mce.h

Fix comment to match the actual declaration.
Signed-off-by: NBorislav Petkov <borislav.petkov@amd.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

arch/x86/include/asm/mce.h

@@ -9,7 +9,7 @@
  */
 
 #define MCG_BANKCNT_MASK	0xff         /* Number of Banks */
-#define MCG_CTL_P		(1ULL<<8)    /* MCG_CAP register available */
+#define MCG_CTL_P		(1ULL<<8)    /* MCG_CTL register available */
 #define MCG_EXT_P		(1ULL<<9)    /* Extended registers available */
 #define MCG_CMCI_P		(1ULL<<10)   /* CMCI supported */
 #define MCG_EXT_CNT_MASK	0xff0000     /* Number of Extended registers */