mozilla-headless-services: Convert to SRCPV

Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

meta/packages/mozilla-headless/mozilla-headless-services_git.bb

@@ -1,6 +1,6 @@
 SRC_URI = "git://git.moblin.org/mozilla-headless-services.git;protocol=git \
            file://confighack.patch;patch=1"
-PV = "0.0+git${SRCREV}"
+PV = "0.1+git${SRCPV}"
 PR = "r1"
 
 DEPENDS = "glib-2.0 dbus mozilla-headless json-glib"