drm/amd/display: dcn2 dmcu wait_for_loop update with dispclk.

[Description]
DMUB is using DPREF CLK, but DMCU still use displayclk.
This is for updating DMCU wait_for_loop after display clock change.
Signed-off-by: Charlene Liu <charlene.liu@amd.com>
Reviewed-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c

@@ -175,6 +175,7 @@ void dcn2_update_clocks(struct clk_mgr *clk_mgr_base,
 	bool update_dispclk = false;
 	bool enter_display_off = false;
 	bool dpp_clock_lowered = false;
+	struct dmcu *dmcu = clk_mgr_base->ctx->dc->res_pool->dmcu;
 
 	display_count = get_active_display_cnt(dc, context);
 	if (dc->res_pool->pp_smu)
@@ -357,6 +358,7 @@ void dcn20_clk_mgr_construct(
 		 * this works because the int part is on the right edge of the register
 		 * and the frac part is on the left edge
 		 */
+
 		pll_req = dc_fixpt_from_int(pll_req_reg & clk_mgr->clk_mgr_mask->FbMult_int);
 		pll_req.value |= pll_req_reg & clk_mgr->clk_mgr_mask->FbMult_frac;