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/cpufreq.c b/arch/avr32/mach-at32ap/cpufreq.c
index 024c586..6277433 100644
--- a/arch/avr32/mach-at32ap/cpufreq.c
+++ b/arch/avr32/mach-at32ap/cpufreq.c
@@ -18,6 +18,7 @@
 #include <linux/io.h>
 #include <linux/clk.h>
 #include <linux/err.h>
+#include <linux/export.h>
 #include <asm/system.h>
 
 static struct clk *cpuclk;