checkpatch: return is not a function -- parentheses for casts are ok too

Casts require parentheses so it is possible to have something like this:

	return (int)(*a);

This miss trips the complexity function.  Ensure that the two separate
parenthesised sections are not coelesced.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>