xl2tpd: Update git recipe and add release recipe

The previous xl2tpd was significantly out of date, so update the git
recipe and add in a release recipe for anyone looking to use the latest
stable release.

Signed-off-by: Joe MacDonald <joe_macdonald@mentor.com>

meta-networking/recipes-protocols/xl2tpd/xl2tpd_1.3.6.bb

@@ -0,0 +1,3 @@
+require xl2tpd.inc
+
+SRC_URI = "git://github.com/xelerance/xl2tpd.git;protocol=git;tag=v${PV}"

meta-networking/recipes-protocols/xl2tpd/xl2tpd_git.bb

@@ -1,5 +1,5 @@
 require xl2tpd.inc
 PR = "${INC_PR}.0"
 
-SRCREV = "df7e30eb199fc5710faa83866381aea18b66e60c"
+SRCREV = "a96b345962622ea58490924130675df6db062d11"