thermal/drivers/imx8mm: Suppress log message on probe deferral

nvmem_cell_read_u32() may return -EPROBE_DEFER if NVMEM supplier has not
yet been probed. Future reprobe may succeed, so printing:

  i.mx8mm_thermal 30260000.tmu: Failed to read OCOTP nvmem cell (-517).

to the log is confusing. Fix this by using dev_err_probe. This also
elevates the message from warning to error, which is more correct: The
log message is only ever printed in probe error path and probe aborts
afterwards, so it really warrants an error-level message.

Fixes: 4032916488 ("thermal/drivers/imx: Add support for loading calibration data from OCOTP")
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230708112647.2897294-1-a.fatoum@pengutronix.de

drivers/thermal/imx8mm_thermal.c

@@ -178,10 +178,8 @@ static int imx8mm_tmu_probe_set_calib_v1(struct platform_device *pdev,
 	int ret;
 
 	ret = nvmem_cell_read_u32(&pdev->dev, "calib", &ana0);
-	if (ret) {
-		dev_warn(dev, "Failed to read OCOTP nvmem cell (%d).\n", ret);
-		return ret;
-	}
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to read OCOTP nvmem cell\n");
 
 	writel(FIELD_PREP(TASR_BUF_VREF_MASK,
 			  FIELD_GET(ANA0_BUF_VREF_MASK, ana0)) |