phosphor-mapper.bb: bump version

Change-Id: I6746f0e5632f9587d338ec9ef7df221625be8837
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/common/recipes-phosphor/dbus/phosphor-mapper.bb b/common/recipes-phosphor/dbus/phosphor-mapper.bb
index c952f6e..476dca9 100644
--- a/common/recipes-phosphor/dbus/phosphor-mapper.bb
+++ b/common/recipes-phosphor/dbus/phosphor-mapper.bb
@@ -23,7 +23,7 @@
         "
 SRC_URI += "git://github.com/openbmc/phosphor-objmgr"
 
-SRCREV = "7122244c83092499dc8d7836da0a63a08c734856"
+SRCREV = "4a6f9983ca70c30a64958f74ce8dd07cdfc90204"
 
 S = "${WORKDIR}/git"