meta-google: images: Add inplace-gbmc-update

For gbmc override, add inplace-gbmc-update and set it as the
PREFERRED_PROVIDER for virtual/bmc-update.

Google-Bug-Id: 179618452
Google-Bug-Id: 179618500
Signed-off-by: Brandon Kim <brandonkim@google.com>
Change-Id: If8b7a3640b66fd323ee5c1a98619a09463933898
diff --git a/meta-google/conf/distro/gbmc.conf b/meta-google/conf/distro/gbmc.conf
index 354c939..0aca631 100644
--- a/meta-google/conf/distro/gbmc.conf
+++ b/meta-google/conf/distro/gbmc.conf
@@ -16,3 +16,5 @@
 WATCHDOG_PKG ?= "watchdog"
 
 SANITY_TESTED_DISTROS_append = " Debian-rodete \n debian-rodete \n "
+
+PREFERRED_PROVIDER_virtual/bmc-update ?= "inplace-gbmc-update"