Tools: fix style consistency in shell scripts "if [...]; then"

Tools/serial/rc.serial.jinja

@@ -12,8 +12,7 @@ set i {{ command.instance }}
 {% endif -%}
 # get the device & baudrate
 sh $PRT_F
-if [ $SERIAL_DEV != none ]
-then
+if [ $SERIAL_DEV != none ]; then
 {% if not constrained_flash -%}
 	echo "Starting {{ command.label }} on $SERIAL_DEV"
 {% endif -%}

Tools/serial/rc.serial_port.jinja

@@ -4,10 +4,8 @@
 
 set SERIAL_DEV none
 {% for serial_device in serial_devices -%}
-if param compare "$PRT" {{ serial_device.index }}
-then
-	if [ "x$PRT_{{ serial_device.tag }}_" = "x" ]
-	then
+if param compare "$PRT" {{ serial_device.index }}; then
+	if [ "x$PRT_{{ serial_device.tag }}_" = "x" ]; then
 		set SERIAL_DEV {{ serial_device.device }}
 		set BAUD_PARAM SER_{{ serial_device.tag }}_BAUD
 		set PRT_{{ serial_device.tag }}_ 1