sh: Fixup entry-common path breakage for SH-3.

The nommu patches broke the path for the common bits, get it building
for the SH-3/4 case again.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/kernel/cpu/sh3/entry.S

@@ -323,7 +323,7 @@ skip_restore:
 7:	.long	0x30000000
 
 ! common exception handler
-#include "../../entry.S"
+#include "../../entry-common.S"
 	
 ! Exception Vector Base
 !