qextserialport: Bump version and change site

Google Code is a closing forge, qextserialport has already made the move
to Github.

Signed-off-by: Maxime Hadjinlian <maxime.hadjinlian@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/qextserialport/qextserialport.mk

@@ -4,13 +4,10 @@
 #
 ################################################################################
 
-QEXTSERIALPORT_VERSION = 6c47244de4ce6db43c2f05caee957666c951dae1
-QEXTSERIALPORT_SITE = https://qextserialport.googlecode.com/git
-QEXTSERIALPORT_SITE_METHOD = git
-
+QEXTSERIALPORT_VERSION = ada321a9ee463f628e7b781b8ed00ff219152158
+QEXTSERIALPORT_SITE = $(call github,qextserialport,qextserialport,$(QEXTSERIALPORT_VERSION))
 QEXTSERIALPORT_LICENSE = MIT
 QEXTSERIALPORT_LICENSE_FILES = LICENSE
-
 QEXTSERIALPORT_INSTALL_STAGING = YES
 
 ifeq ($(BR2_PACKAGE_QT),y)