drm/amd/display: Drop kdoc markers for some Panel Replay functions

Fixes the below gcc with W=1:
drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dmub_replay.c:262: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Set REPLAY power optimization flags and coasting vtotal.
drivers/gpu/drm/amd/amdgpu/../display/dc/dce/dmub_replay.c:284: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * send Replay general cmd to DMUB.

Fixes: e379787c ("drm/amd/display: Add some functions for Panel Replay")
Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
Cc: Rodrigo Siqueira <rodrigo.siqueira@amd.com>
Cc: Leo Li <sunpeng.li@amd.com>
Cc: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>