drm/i915/lobf: Add lobf enablement in post plane update

Enablement of LOBF is added in post plane update whenever
has_lobf flag is set. As LOBF can be enabled in non-psr
case as well so adding in post plane update. There is no
change of configuring alpm with psr path.

v1: Initial version.
v2: Use encoder-mask to find the associated encoder from
crtc-state. [Jani]
v3: Remove alpm_configure from intel_psr.c. [Jouni]

Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Link: https://lore.kernel.org/r/20250423092334.2294483-3-animesh.manna@intel.com