drm/amd/display: eDP sequence BL off first then DP blank.

drm/amd/display: eDP sequence BL off first then DP blank.

BugLink: https://bugs.launchpad.net/bugs/1814308
Signed-off-by: Charlene Liu <charlene.liu@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 41b497421a1f07ab99814da740984f907747120b)
Signed-off-by: Dan Streetman <ddstreet@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>