media: platform: stm32: defer probe for auxiliary clock

Change stm32-cec driver to defer probe when auxiliary clock
"hdmi-cec" is registered in the system not has not been probed yet.
Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
Reviewed-by: Philippe Cornu <philippe.cornu@st.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/stm32/stm32-cec.c

@@ -302,10 +302,14 @@ static int stm32_cec_probe(struct platform_device *pdev)
 	}
 
 	cec->clk_hdmi_cec = devm_clk_get(&pdev->dev, "hdmi-cec");
+	if (IS_ERR(cec->clk_hdmi_cec) &&
+	    PTR_ERR(cec->clk_hdmi_cec) == -EPROBE_DEFER)
+		return -EPROBE_DEFER;
+
 	if (!IS_ERR(cec->clk_hdmi_cec)) {
 		ret = clk_prepare(cec->clk_hdmi_cec);
 		if (ret) {
-			dev_err(&pdev->dev, "Unable to prepare hdmi-cec clock\n");
+			dev_err(&pdev->dev, "Can't prepare hdmi-cec clock\n");
 			return ret;
 		}
 	}