XBPS_RELVER: embed the latest git rev hash.

configure

@@ -193,6 +193,10 @@ echo "CPPFLAGS = 	-I. -I\$(TOPDIR) -I\$(TOPDIR)/include" >>$CONFIG_MK
 echo "CPPFLAGS +=	-DHAVE_CONFIG_H" >>$CONFIG_MK
 echo "CPPFLAGS +=	-DXBPS_SYSCONF_PATH=\\\"${ETCDIR}\\\"" >>$CONFIG_MK
 echo "CPPFLAGS +=	-DXBPS_VERSION=\\\"${VERSION}\\\"" >>$CONFIG_MK
+if [ -d .git ]; then
+	_gitrev=$(git rev-parse master)
+	echo "CPPFLAGS += -DXBPS_GIT=\\\"${_gitrev}\\\"" >>$CONFIG_MK
+fi
 
 if [ -n "$DEBUG" -a "$DEBUG" != no -a "$DEBUG" != false ]; then
 	echo "Building with debugging symbols."