UPSTREAM: drm/edid: Fix parsing of EDID 1.4 Established Timings III descriptor

UPSTREAM: drm/edid: Fix parsing of EDID 1.4 Established Timings III descriptor

The EDID 1.4 specification section 3.10.3.9 defines an Established Timings III
descriptor (tag #F7h). The parsing of this descriptor by drm_est3_modes() is
off by one byte: the offset of the first timing bitmap is 6, not 5.

Change-Id: Ic24532d54245e035feb474309a609d7efb330658
Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160328002258.E75DF6E35D@gabe.freedesktop.org
Signed-off-by: Zheng Yang <zhengyang@rock-chips.com>
(cherry picked from commit f3a32d74ef733e1ed1a0b804c17ec27081e0ff37)