Bump mapper and rest server revisions

Fixes for freedesktop ObjectManager signal handling.
diff --git a/common/recipes-phosphor/dbus/obmc-mapper.bb b/common/recipes-phosphor/dbus/obmc-mapper.bb
index 37c9c3f..323a179 100644
--- a/common/recipes-phosphor/dbus/obmc-mapper.bb
+++ b/common/recipes-phosphor/dbus/obmc-mapper.bb
@@ -20,6 +20,6 @@
         git://github.com/openbmc/phosphor-objmgr \
         "
 
-SRCREV = "6aed08d480aa1e022df14d48b7a54f5b1790e7d9"
+SRCREV = "3f7aa329568d8f191baeeefa4a63dbb19cf26338"
 
 S = "${WORKDIR}/git"