Hexagon: misc compile warning/error cleanup due to missing headers

Fixed warnings/errors for EXPORT_SYMBOL, linux_binprm, elf related
defines

Signed-off-by: Richard Kuo <rkuo@codeaurora.org>
diff --git a/arch/hexagon/kernel/dma.c b/arch/hexagon/kernel/dma.c
index 3730221..0f2367c 100644
--- a/arch/hexagon/kernel/dma.c
+++ b/arch/hexagon/kernel/dma.c
@@ -22,6 +22,7 @@
 #include <linux/bootmem.h>
 #include <linux/genalloc.h>
 #include <asm/dma-mapping.h>
+#include <linux/module.h>
 
 struct dma_map_ops *dma_ops;
 EXPORT_SYMBOL(dma_ops);