drm/i915: Rename PLANE_CTL_DECOMPRESSION_ENABLE

Rename PLANE_CTL_DECOMPRESSION_ENABLE to resemble the bpsec name -
PLANE_CTL_RENDER_DECOMPRESSION_ENABLE

Suggested-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180822015053.1420-2-dhinakaran.pandiyan@intel.com