drm/panel: ltk050h3146w: use dev_err_probe wherever possible

This is only a cosmetic change.

This replaces a hand-crafted EPROBE_DEFER handling for deciding to print
an error message with dev_err_probe.

A side-effect is that dev_err_probe also adds a debug message when it's
not EPROBE_DEFER, but this is seen as an improvement.

Cc: Quentin Schulz <[e-mail]>
Signed-off-by: Quentin Schulz <[e-mail]>
Reviewed-by: Christophe JAILLET <[e-mail]>
Signed-off-by: Heiko Stuebner <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/panel/panel-leadtek-ltk050h3146w.c

···
 		return dev_err_probe(dev, PTR_ERR(ctx->reset_gpio), "cannot get reset gpio\n");
 
 	ctx->vci = devm_regulator_get(dev, "vci");
-	if (IS_ERR(ctx->vci)) {
-		ret = PTR_ERR(ctx->vci);
-		if (ret != -EPROBE_DEFER)
-			dev_err(dev, "Failed to request vci regulator: %d\n", ret);
-		return ret;
-	}
+	if (IS_ERR(ctx->vci))
+		return dev_err_probe(dev, PTR_ERR(ctx->vci), "Failed to request vci regulator\n");
 
 	ctx->iovcc = devm_regulator_get(dev, "iovcc");
-	if (IS_ERR(ctx->iovcc)) {
-		ret = PTR_ERR(ctx->iovcc);
-		if (ret != -EPROBE_DEFER)
-			dev_err(dev, "Failed to request iovcc regulator: %d\n", ret);
-		return ret;
-	}
+	if (IS_ERR(ctx->iovcc))
+		return dev_err_probe(dev, PTR_ERR(ctx->iovcc),
+				     "Failed to request iovcc regulator\n");
 
 	mipi_dsi_set_drvdata(dsi, ctx);