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/board-dm644x-evm.c b/arch/arm/mach-davinci/board-dm644x-evm.c
index a005e769..28fafa78 100644
--- a/arch/arm/mach-davinci/board-dm644x-evm.c
+++ b/arch/arm/mach-davinci/board-dm644x-evm.c
@@ -23,6 +23,7 @@
 #include <linux/phy.h>
 #include <linux/clk.h>
 #include <linux/videodev2.h>
+#include <linux/export.h>
 
 #include <media/tvp514x.h>