drm: Rename DP_PSR_SELECTIVE_UPDATE to better mach eDP spec

DP_PSR_EN_CFG bit 5 aka "Selective Update Region Scan Line Capture
Indication" in eDP spec has a ambiguous name, so renaming to better
match specification.

While at it, replacing bit shit by BIT() macro and adding the version
some registers were added to eDP specification.

Cc: <dri-devel@lists.freedesktop.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210421220224.200729-1-jose.souza@intel.com