drm/i915/lrc: switch to _MASKED_BIT_ENABLE() and _MASKED_BIT_DISABLE()

drm/i915/lrc: switch to _MASKED_BIT_ENABLE() and _MASKED_BIT_DISABLE()

Since it's now possible to use _MASKED_BIT_ENABLE() and
_MASKED_BIT_DISABLE() in the array initializer, switch to them. This
allows us to remove __MASKED_FIELD() macro.

Reviewed-by: Michał Grzelak <michal.grzelak@intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patch.msgid.link/733568f8a6155b6e2da1dcdce9d21d6aab881449.1772042022.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>