drivers/gpu/drm/radeon/radeon_atombios.c: range check issues

This change makes the array larger, "MAX_SUPPORTED_TV_TIMING_V1_2" is 3
and the original size "MAX_SUPPORTED_TV_TIMING" is 2.

Also there were checks that were off by one.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>