drm/i915/glk: Add new bit fields in MIPI CTRL register

v2: Addressed Jani's Review comments (renamed bit field macros)

Signed-off-by: Deepak M <m.deepak@intel.com>
Signed-off-by: Madhav Chauhan <madhav.chauhan@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1481792500-30863-2-git-send-email-madhav.chauhan@intel.com