drm/exynos: use logical AND in exynos_drm_plane_check_size()

The current bitwise AND should result in the same assembler
but this is what the code is actually supposed to do.

Signed-off-by: Tobias Jakobi <[e-mail]>
Signed-off-by: Inki Dae <[e-mail]>

drivers/gpu/drm/exynos/exynos_drm_plane.c

···
 	    state->v_ratio == (1 << 15))
 		height_ok = true;
 
-	if (width_ok & height_ok)
+	if (width_ok && height_ok)
 		return 0;
 
 	DRM_DEBUG_KMS("scaling mode is not supported");