rtc: use %ph for short hex dumps

This makes the generated code slightly smaller.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index aa705bb..cf685f6 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -460,13 +460,8 @@
 		return -EIO;
 	}
 
-	dev_dbg(dev, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
-			"alarm read",
-			ds1307->regs[0], ds1307->regs[1],
-			ds1307->regs[2], ds1307->regs[3],
-			ds1307->regs[4], ds1307->regs[5],
-			ds1307->regs[6], ds1307->regs[7],
-			ds1307->regs[8]);
+	dev_dbg(dev, "%s: %4ph, %3ph, %2ph\n", "alarm read",
+		&ds1307->regs[0], &ds1307->regs[4], &ds1307->regs[7]);
 
 	/*
 	 * report alarm time (ALARM1); assume 24 hour and day-of-month modes,
@@ -522,12 +517,8 @@
 	control = ds1307->regs[7];
 	status = ds1307->regs[8];
 
-	dev_dbg(dev, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
-			"alarm set (old status)",
-			ds1307->regs[0], ds1307->regs[1],
-			ds1307->regs[2], ds1307->regs[3],
-			ds1307->regs[4], ds1307->regs[5],
-			ds1307->regs[6], control, status);
+	dev_dbg(dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)",
+		&ds1307->regs[0], &ds1307->regs[4], control, status);
 
 	/* set ALARM1, using 24 hour and day-of-month modes */
 	buf[0] = bin2bcd(t->time.tm_sec);