drm/bridge: fix kdoc syntax

Use the correct kdoc syntax for bullet list.

Fixes kdoc error and warning:

  Documentation/gpu/drm-kms-helpers:197: ./drivers/gpu/drm/drm_bridge.c:1519: ERROR: Unexpected indentation. [docutils]
  Documentation/gpu/drm-kms-helpers:197: ./drivers/gpu/drm/drm_bridge.c:1521: WARNING: Block quote ends without a blank line; unexpected unindent. [docutils]

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202512302319.1PGGt3CN-lkp@intel.com/
Fixes: 9da0e06 ("drm/bridge: deprecate of_drm_find_bridge()")
Reviewed-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Link: https://patch.msgid.link/20251231-drm-bridge-alloc-getput-drm_of_find_bridge-kdoc-fix-v1-1-193a03f0609c@bootlin.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>

Author: lucaceresoli

drivers/gpu/drm/drm_bridge.c

@@ -1518,11 +1518,14 @@ EXPORT_SYMBOL(of_drm_find_and_get_bridge);
  * The bridge returned by this function is not refcounted. This is
  * dangerous because the bridge might be deallocated even before the caller
  * has a chance to use it. To use this function you have to do one of:
+ *
  * - get a reference with drm_bridge_get() as soon as possible to
  *   minimize the race window, and then drm_bridge_put() when no longer
  *   using the pointer
+ *
  * - not call drm_bridge_get() or drm_bridge_put() at all, which used to
  *   be the correct practice before dynamic bridge lifetime was introduced
+ *
  * - again, convert to of_drm_find_and_get_bridge(), which is the only safe
  *   thing to do
  *