[ARM] 3448/1: [S3C2410] Settle delay when _enabling_ USB PLL

Patch from Ben Dooks

Fix the bug in the UPLL enable code which should
have put a 200uS delay in if enabling the USB PLL
from the state where it is off.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>