drm/exynos/hdmi: add a missing tab

Smatch warns that the if statement isn't indented.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20160512195457.GA19095@mwanda