[ARM] S3C64XX: Mask the pll values correctly

Correct the PLL field masks to ensure the PLL functions return the
right value.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
[ben-linux@fluff.org: improve the description text]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
1 file changed