arm: Add export.h to ARM specific files as required.

These files all make use of one of the EXPORT_SYMBOL variants
or the THIS_MODULE macro.  So they will need <linux/export.h>

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/arch/arm/mach-davinci/cpufreq.c b/arch/arm/mach-davinci/cpufreq.c
index 41669ec..5bba707 100644
--- a/arch/arm/mach-davinci/cpufreq.c
+++ b/arch/arm/mach-davinci/cpufreq.c
@@ -24,6 +24,7 @@
 #include <linux/err.h>
 #include <linux/clk.h>
 #include <linux/platform_device.h>
+#include <linux/export.h>
 
 #include <mach/hardware.h>
 #include <mach/cpufreq.h>