[MIPS] SB1250: Fix bugs/warnings by creative use of volatile.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/include/asm-mips/sibyte/sb1250.h b/include/asm-mips/sibyte/sb1250.h
index dfb29e1..494aa65 100644
--- a/include/asm-mips/sibyte/sb1250.h
+++ b/include/asm-mips/sibyte/sb1250.h
@@ -67,6 +67,6 @@
 
 #endif
 
-#define IOADDR(a) ((volatile void __iomem *)(IO_BASE + (a)))
+#define IOADDR(a) ((void __iomem *)(IO_BASE + (a)))
 
 #endif