avr32: add export.h to arch/avr32 for EXPORT_SYMBOL/THIS_MODULE

Add it in where the module.h implicit presence was doing
the job before.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/arch/avr32/mach-at32ap/clock.c b/arch/avr32/mach-at32ap/clock.c
index 86925fd..23b1a97 100644
--- a/arch/avr32/mach-at32ap/clock.c
+++ b/arch/avr32/mach-at32ap/clock.c
@@ -13,6 +13,7 @@
  */
 #include <linux/clk.h>
 #include <linux/err.h>
+#include <linux/export.h>
 #include <linux/device.h>
 #include <linux/string.h>
 #include <linux/list.h>