MIPS: Fix build error due to missing inclusion of <linux/export.h>.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/pci/pci-alchemy.c b/arch/mips/pci/pci-alchemy.c
index 4ee5710..b5ce041 100644
--- a/arch/mips/pci/pci-alchemy.c
+++ b/arch/mips/pci/pci-alchemy.c
@@ -7,6 +7,7 @@
  * Support for all devices (greater than 16) added by David Gathright.
  */
 
+#include <linux/export.h>
 #include <linux/types.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>