disp: msm: replace PTR_RET with PTR_ERR_OR_ZERO

Commit fad7c9020948 ("err.h: remove deprecated PTR_RET for good")
deprecated PTR_RET. This change updates the msm driver by
replacing it with PTR_ERR_OR_ZERO.

Change-Id: Ibe8cefd7b9ce27dc63886eb3861aab5fc8ba268a
Signed-off-by: Samantha Tran <samtran@codeaurora.org>
Signed-off-by: Nilaan Gunabalachandran <ngunabal@codeaurora.org>

msm/dsi/dsi_panel.c

@@ -78,7 +78,7 @@ static int dsi_panel_vreg_get(struct dsi_panel *panel)
 	for (i = 0; i < panel->power_info.count; i++) {
 		vreg = devm_regulator_get(panel->parent,
 					  panel->power_info.vregs[i].vreg_name);
-		rc = PTR_RET(vreg);
+		rc = PTR_ERR_OR_ZERO(vreg);
 		if (rc) {
 			DSI_ERR("failed to get %s regulator\n",
 			       panel->power_info.vregs[i].vreg_name);