drm/amd/pm/powerplay/hwmgr/vega20_hwmgr: Fix legacy function header formatting

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/amd/amdgpu/../pm/powerplay/hwmgr/vega20_hwmgr.c:781: warning: Function parameter or member 'hwmgr' not described in 'vega20_init_smc_table'

Cc: Evan Quan <evan.quan@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega20_hwmgr.c

@@ -771,12 +771,11 @@ static int vega20_setup_default_dpm_tables(struct pp_hwmgr *hwmgr)
 }
 
 /**
-* Initializes the SMC table and uploads it
-*
-* @param    hwmgr  the address of the powerplay hardware manager.
-* @param    pInput  the pointer to input data (PowerState)
-* @return   always 0
-*/
+ * Initializes the SMC table and uploads it
+ *
+ * @hwmgr:  the address of the powerplay hardware manager.
+ * return:  always 0
+ */
 static int vega20_init_smc_table(struct pp_hwmgr *hwmgr)
 {
 	int result;