drm/amdgpu/userq: fix user_queue parameters list

drm/amdgpu/userq: fix user_queue parameters list

Sphinx reports htmldocs warning:

Documentation/gpu/amdgpu/module-parameters:7: drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c:1119: ERROR: Unexpected indentation. [docutils]

Fix the warning by using reST bullet list syntax for user_queue
parameter options, separated from preceding paragraph by a blank
line.

Fixes: fb20954c9717 ("drm/amdgpu/userq: rework driver parameter")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/linux-next/20250422202956.176fb590@canb.auug.org.au/
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>