[media] s5p-jpeg: Fix sysmmu page fault

This patch fixes jpeg sysmmu page fault on Exynos4x12 SoCs.
During encoding Exynos4x12 SoCs access wider memory area
than it results from Image_x and Image_y values written to
the JPEG_IMAGE_SIZE register. In order to avoid sysmmu page
fault apply proper output buffer size alignment.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>