pmic: pfuze100: Change error message level to debug

In some cases U-Boot runs the same binary on different board versions.

In wandboard, for example, there are versions with the PFUZE100 PMIC
populated and others without it.

When the PMIC is not present, it is not really useful to get PMIC error,
so change the error message level to debug instead.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Tested-by: Heiko Schocher <hs@denx.de>
diff --git a/drivers/power/pmic/pfuze100.c b/drivers/power/pmic/pfuze100.c
index 6cf5f35..db630f3 100644
--- a/drivers/power/pmic/pfuze100.c
+++ b/drivers/power/pmic/pfuze100.c
@@ -41,7 +41,7 @@
 static int pfuze100_read(struct udevice *dev, uint reg, uint8_t *buff, int len)
 {
 	if (dm_i2c_read(dev, reg, buff, len)) {
-		pr_err("read error from device: %p register: %#x!\n", dev, reg);
+		debug("read error from device: %p register: %#x!\n", dev, reg);
 		return -EIO;
 	}