dhcpcd.exe: Flush any configured IP addresses on shutdown

This allows us to start with a fresh interface every time dhcpcd is
being restarted.

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

src/initscripts/networking/dhcpcd.exe

@@ -84,6 +84,11 @@ dhcpcd_down()
 			run_subdir ${rc_base}/init.d/networking/red.down/
 		fi
 	fi
+
+	# Remove any configured IP address from the device
+	ip addr flush dev "${interface}" &>/dev/null
+
+	return 0
 }
 
 # Called when dhcpcd relies on a third party to configure an IP address