Blackfin: pull in asm/io.h in ksyms for prototypes

Make sure we pull in asm/io.h when exporting symbols for the I/O functions
so we don't end up with a build failure due to missing prototypes.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

arch/blackfin/kernel/bfin_ksyms.c

@@ -10,6 +10,7 @@
 #include <linux/uaccess.h>
 
 #include <asm/cacheflush.h>
+#include <asm/io.h>
 
 /* Allow people to have their own Blackfin exception handler in a module */
 EXPORT_SYMBOL(bfin_return_from_exception);