Blackfin arch: include linux/mm.h since we use PAGE_ALIGN and such

Signed-off-by: NMike Frysinger <vapier.adi@gmail.com>
Signed-off-by: NBryan Wu <cooloney@kernel.org>

arch/blackfin/kernel/setup.c

@@ -13,6 +13,7 @@
 #include <linux/bootmem.h>
 #include <linux/seq_file.h>
 #include <linux/cpu.h>
+#include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/tty.h>
 #include <linux/pfn.h>