[ARM] pxa: avoid polluting the kernel's namespace

Avoid unnecessarily pollution of the kernel's namespace by avoiding
mach/hardware.h.  Include this header file where necessary.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/net/smc91x.h b/drivers/net/smc91x.h
index a07cc93..22576e0 100644
--- a/drivers/net/smc91x.h
+++ b/drivers/net/smc91x.h
@@ -528,6 +528,7 @@
  */
 #include <linux/dma-mapping.h>
 #include <asm/dma.h>
+#include <mach/hardware.h>
 #include <mach/pxa-regs.h>
 
 #ifdef SMC_insl