[media] s5p-tv: Add missing braces around sizeof in hdmiphy_drv.c

Fixes the following checkpatch warning:
WARNING: sizeof *ctx should be sizeof(*ctx)
FILE: media/platform/s5p-tv/hdmiphy_drv.c:287:
	ctx = kzalloc(sizeof *ctx, GFP_KERNEL);

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Tomasz Stanislawski <t.stanislaws@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>