sh: module_alloc() should be using vmalloc_exec().

SH-X2 extended mode TLB allows for toggling of the exec bit, so make
sure we are using the right protection bits for module space there
also.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/kernel/module.c

@@ -37,7 +37,8 @@ void *module_alloc(unsigned long size)
 {
 	if (size == 0)
 		return NULL;
-	return vmalloc(size);
+
+	return vmalloc_exec(size);
 }