meta-ibm: disable insecure-tftp-update feature

Disable insecure-tftp-update feature since its not used anymore.

Change-Id: I8ea8063d8519c845edbc537fc24be45dc2fcdd41
Signed-off-by: Jagpal Singh Gill <paligill@gmail.com>
diff --git a/meta-ibm/recipes-phosphor/interfaces/bmcweb_%.bbappend b/meta-ibm/recipes-phosphor/interfaces/bmcweb_%.bbappend
index 5253fe9..0116afa 100644
--- a/meta-ibm/recipes-phosphor/interfaces/bmcweb_%.bbappend
+++ b/meta-ibm/recipes-phosphor/interfaces/bmcweb_%.bbappend
@@ -1,5 +1,4 @@
 EXTRA_OEMESON:append = " \
-    -Dinsecure-tftp-update=enabled \
     -Dibm-management-console=enabled \
     -Dredfish-dump-log=enabled \
     -Dredfish-oem-manager-fan-data=disabled \