x86: pci-calgary_64.c: make a variable static

"debugging" is a horrible name for a global variable - thankfully it can
become static.

Also put it out of __read_mostly so that gcc no longer has to emit it
at all.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/pci-calgary_64.c

@@ -183,7 +183,7 @@ static struct calgary_bus_info bus_info[MAX_PHB_BUS_NUM] = { { NULL, 0, 0 }, };
 
 /* enable this to stress test the chip's TCE cache */
 #ifdef CONFIG_IOMMU_DEBUG
-int debugging __read_mostly = 1;
+static int debugging = 1;
 
 static inline unsigned long verify_bit_range(unsigned long* bitmap,
 	int expected, unsigned long start, unsigned long end)
@@ -202,7 +202,7 @@ static inline unsigned long verify_bit_range(unsigned long* bitmap,
 	return ~0UL;
 }
 #else /* debugging is disabled */
-int debugging __read_mostly = 0;
+static int debugging;
 
 static inline unsigned long verify_bit_range(unsigned long* bitmap,
 	int expected, unsigned long start, unsigned long end)