rtc: isl12022: Join string literals back

For easy grepping on debug purposes join string literals back in
the messages.

While at it, drop __func__ parameter from unique enough dev_dbg()
message as Dynamic Debug can retrieve this at run time.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20230110140806.87432-5-andriy.shevchenko@linux.intel.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

drivers/rtc/rtc-isl12022.c

@@ -143,16 +143,12 @@ static int isl12022_rtc_read_time(struct device *dev, struct rtc_time *tm)
 
 	if (buf[ISL12022_REG_SR] & (ISL12022_SR_LBAT85 | ISL12022_SR_LBAT75)) {
 		dev_warn(dev,
-			 "voltage dropped below %u%%, "
-			 "date and time is not reliable.\n",
+			 "voltage dropped below %u%%, date and time is not reliable.\n",
 			 buf[ISL12022_REG_SR] & ISL12022_SR_LBAT85 ? 85 : 75);
 	}
 
 	dev_dbg(dev,
-		"%s: raw data is sec=%02x, min=%02x, hr=%02x, "
-		"mday=%02x, mon=%02x, year=%02x, wday=%02x, "
-		"sr=%02x, int=%02x",
-		__func__,
+		"raw data is sec=%02x, min=%02x, hr=%02x, mday=%02x, mon=%02x, year=%02x, wday=%02x, sr=%02x, int=%02x",
 		buf[ISL12022_REG_SC],
 		buf[ISL12022_REG_MN],
 		buf[ISL12022_REG_HR],