Fix compile error

...as suggested by Peter Pearse

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/cpu/arm1136/omap24xx/interrupts.c b/cpu/arm1136/omap24xx/interrupts.c
index a50fa39..b9a8b93 100644
--- a/cpu/arm1136/omap24xx/interrupts.c
+++ b/cpu/arm1136/omap24xx/interrupts.c
@@ -37,7 +37,7 @@
 #define TIMER_LOAD_VAL 0
 
 /* macro to read the 32 bit timer */
-#define READ_TIMER (*(volatile ulong *)(CFG_TIMERBASE+TCRR))
+#define READ_TIMER (*((volatile ulong *)(CFG_TIMERBASE+TCRR)))
 
 static ulong timestamp;
 static ulong lastinc;