drm/i915: pass dev_priv explicitly to PORT_ALPM_LFPS_CTL

Avoid the implicit dev_priv local variable use, and pass dev_priv
explicitly to the PORT_ALPM_LFPS_CTL register macro.

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/f8a3bbade94258852b8129c5f5918fb06ceab54b.1714471597.git.jani.nikula@intel.com


Signed-off-by: Jani Nikula <jani.nikula@intel.com>