drm/amd/display: dc_hw_sequencer.c: remove kernel-doc comments

drm/amd/display: dc_hw_sequencer.c: remove kernel-doc comments

Change comments from kernel-doc style "/**" to normal C comments
"/*" since the comments are not in kernel-doc format.
This fixes around 39 kernel-doc warnings like this one:

drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c:1322: warning:
 This comment starts with '/**', but isn't a kernel-doc comment.
 Refer Documentation/doc-guide/kernel-doc.rst

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202511062036.Ry8Z2APc-lkp@intel.com/
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>