update phosphor-event recipe

Update phosphor-event to the latest revision including support
for limmiiting the size of the event log DB.

Signed-off-by: Milton Miller <miltonm@us.ibm.com>
diff --git a/meta-phosphor/common/recipes-phosphor/obmc-phosphor-event/obmc-phosphor-event.bb b/meta-phosphor/common/recipes-phosphor/obmc-phosphor-event/obmc-phosphor-event.bb
index 5ce5818..06422cf 100644
--- a/meta-phosphor/common/recipes-phosphor/obmc-phosphor-event/obmc-phosphor-event.bb
+++ b/meta-phosphor/common/recipes-phosphor/obmc-phosphor-event/obmc-phosphor-event.bb
@@ -13,7 +13,7 @@
 
 SRC_URI += "git://github.com/openbmc/phosphor-event"
 
-SRCREV = "127c8cf513ba9ed6bcc460fbea29b36eb8d23bac"
+SRCREV = "b7ea1b9f322f705e4f1a086367733f8a6d46eb96"
 
 RDEPENDS_${PN} += "libsystemd"
 DEPENDS += "systemd"