bmcweb: Set BMCWEB_HTTP_REQ_BODY_LIMIT_MB to 400

By default, bmcweb limits the size of the http request body to 30MB
to limit a DOS attack based on a large file size.

OpenBMC supports "System" or "bundled" images that contain two or more
firmware images. For OpenPOWER systems, these include the BMC and Host
firmware making the resulting image greater than the default 30MB.

A configurable option (BMCWEB_HTTP_REQ_BODY_LIMIT_MB) was added to
bmcweb to be able to change this limit:
https://github.com/openbmc/bmcweb/commit/0e1cf26b1cd98e0ec069e6187434fcabf1e9c200

Set this option to an arbitrary size of 400MB since the size of /tmp
for currently supported OpenBMC systems is ~460MB and /tmp is where
the uploaded image files are stored.

(From meta-openpower rev: 18c94c3554002fc2242f268b9eb449ec660ee92b)

Change-Id: I66dda4fa598db0d5ea8216e386d8e90c544e6bc2
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/meta-openpower/recipes-phosphor/interfaces/bmcweb_%.bbappend b/meta-openpower/recipes-phosphor/interfaces/bmcweb_%.bbappend
index bc134ae..632d240 100644
--- a/meta-openpower/recipes-phosphor/interfaces/bmcweb_%.bbappend
+++ b/meta-openpower/recipes-phosphor/interfaces/bmcweb_%.bbappend
@@ -1,4 +1,5 @@
 EXTRA_OECMAKE_append_df-openpower = " \
     -DBMCWEB_ENABLE_REDFISH_DBUS_LOG_ENTRIES=ON \
     -DBMCWEB_ENABLE_LOGGING_MW=ON \
+    -DBMCWEB_HTTP_REQ_BODY_LIMIT_MB=400 \
     "