drm/i915/dsi: Fix swapping of MIPI_SEQ_DEASSERT_RESET / MIPI_SEQ_ASSERT_RESET

Looking at the ADF code from the Android kernel sources for a
cherrytrail tablet I noticed that it is calling the
MIPI_SEQ_ASSERT_RESET sequence from the panel prepare hook.

Until commit b1cb1bd2 ("drm/i915/dsi: update reset and power sequences
in panel prepare/unprepare hooks") the mainline i915 code was doing the
same. That commits effectively swaps the calling of MIPI_SEQ_ASSERT_RESET /
MIPI_SEQ_DEASSERT_RESET.

Looking at the naming of the sequences that is the right thing to do,
but the problem is, that the old mainline code and the ADF code was
actually calling the right sequence (tested on a cube iwork8 air tablet),
and the swapping of the calling breaks things.

This breakage was likely not noticed in testing because on cherrytrail,
currently chv_exec_gpio ends up disabling the gpio pins rather then
setting them (this is fixed in the next patch in this patch-set).

This commit fixes the swapping by fixing MIPI_SEQ_ASSERT/DEASSERT_RESET's
places in the enum defining them, so that their (new) names match their
actual use.

Changes in v2:
-Add a comment to the enum explaining that the assert/reassert names
 are swapped in the spec

Fixes: b1cb1bd2

 ("drm/i915/dsi: update reset and power sequences...")
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161202150128.29871-1-hdegoede@redhat.com
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
(cherry picked from commit 2b8208ac

)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>