[ARM] 3994/1: ixp23xx: fix handling of pci master aborts

The PCI master abort handling issue that affected ixp2000 also
affects ixp23xx.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-ixp23xx/pci.c

@@ -36,7 +36,7 @@
 
 extern int (*external_fault) (unsigned long, struct pt_regs *);
 
-static int pci_master_aborts = 0;
+static volatile int pci_master_aborts = 0;
 
 #ifdef DEBUG
 #define DBG(x...)	printk(x)