drm/amd/display: Remove redundant checks for res_pool->dccg

The null checks for res_pool->dccg are redundant as it was already
dereferenced previously, as reported by Coverity; therefore the
null checks are removed.

This fixes 6 REVERSE_INULL issues reported by Coverity.
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/hwss/dcn201/dcn201_hwseq.c

@@ -240,7 +240,7 @@ void dcn201_init_hw(struct dc *dc)
 		res_pool->ref_clocks.xtalin_clock_inKhz =
 			dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency;
 
-		if (res_pool->dccg && res_pool->hubbub) {
+		if (res_pool->hubbub) {
 			(res_pool->dccg->funcs->get_dccg_ref_freq)(res_pool->dccg,
 					dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency,
 					&res_pool->ref_clocks.dccg_ref_clock_inKhz);

drivers/gpu/drm/amd/display/dc/hwss/dcn30/dcn30_hwseq.c

@@ -656,7 +656,7 @@ void dcn30_init_hw(struct dc *dc)
 		res_pool->ref_clocks.xtalin_clock_inKhz =
 				dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency;
 
-		if (res_pool->dccg && res_pool->hubbub) {
+		if (res_pool->hubbub) {
 
 			(res_pool->dccg->funcs->get_dccg_ref_freq)(res_pool->dccg,
 					dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency,

drivers/gpu/drm/amd/display/dc/hwss/dcn31/dcn31_hwseq.c

@@ -132,7 +132,7 @@ void dcn31_init_hw(struct dc *dc)
 		res_pool->ref_clocks.xtalin_clock_inKhz =
 				dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency;
 
-		if (res_pool->dccg && res_pool->hubbub) {
+		if (res_pool->hubbub) {
 
 			(res_pool->dccg->funcs->get_dccg_ref_freq)(res_pool->dccg,
 					dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency,

drivers/gpu/drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c

@@ -806,7 +806,7 @@ void dcn32_init_hw(struct dc *dc)
 		res_pool->ref_clocks.xtalin_clock_inKhz =
 				dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency;
 
-		if (res_pool->dccg && res_pool->hubbub) {
+		if (res_pool->hubbub) {
 			(res_pool->dccg->funcs->get_dccg_ref_freq)(res_pool->dccg,
 					dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency,
 					&res_pool->ref_clocks.dccg_ref_clock_inKhz);

drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c

@@ -188,7 +188,7 @@ void dcn35_init_hw(struct dc *dc)
 		res_pool->ref_clocks.xtalin_clock_inKhz =
 				dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency;
 
-		if (res_pool->dccg && res_pool->hubbub) {
+		if (res_pool->hubbub) {
 
 			(res_pool->dccg->funcs->get_dccg_ref_freq)(res_pool->dccg,
 				dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency,

drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c

@@ -259,7 +259,7 @@ void dcn401_init_hw(struct dc *dc)
 		res_pool->ref_clocks.xtalin_clock_inKhz =
 				dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency;
 
-		if (res_pool->dccg && res_pool->hubbub) {
+		if (res_pool->hubbub) {
 			(res_pool->dccg->funcs->get_dccg_ref_freq)(res_pool->dccg,
 					dc->ctx->dc_bios->fw_info.pll_info.crystal_frequency,
 					&res_pool->ref_clocks.dccg_ref_clock_inKhz);