drm/i915/fbdev: Hold runtime PM ref during fbdev BO creation

drm/i915/fbdev: Hold runtime PM ref during fbdev BO creation

During fbdev probe, the xe driver allocates and pins a framebuffer
BO (via xe_bo_create_pin_map_novm() → xe_ggtt_insert_bo()).

Without a runtime PM reference, xe_pm_runtime_get_noresume() warns about
missing outer PM protection as below:

	xe 0000:03:00.0: [drm] Missing outer runtime PM protection

Acquire a runtime PM reference before framebuffer allocation to ensure
xe_ggtt_insert_bo()  executes  under active runtime PM context.

Changes in v2:
 - Update commit message to add Fixes tag (Jani Nikula)

Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6350
Fixes: 44e694958b95 ("drm/xe/display: Implement display support")
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Dibin Moolakadan Subrahmanian <dibin.moolakadan.subrahmanian@intel.com>
Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patch.msgid.link/20251111135403.3415947-1-dibin.moolakadan.subrahmanian@intel.com