meta-google: gbmc-bridge: Restrict network from /72 to /76

We can have multiple gBMC networks within one "machine". This allows us
to have multiple address sets.

Change-Id: I5b18b7822f50bb0570e1aa5a70ac47036694d922
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/meta-google/recipes-google/ncsi/files/gbmc-ncsi-br-pub-addr.sh.in b/meta-google/recipes-google/ncsi/files/gbmc-ncsi-br-pub-addr.sh.in
index 961da50..b04f2aa 100644
--- a/meta-google/recipes-google/ncsi/files/gbmc-ncsi-br-pub-addr.sh.in
+++ b/meta-google/recipes-google/ncsi/files/gbmc-ncsi-br-pub-addr.sh.in
@@ -56,7 +56,7 @@
 Route=$ncsi_pfx/80
 LifetimeSec=60
 [Route]
-Destination=$stateless_pfx/72
+Destination=$stateless_pfx/76
 Type=unreachable
 Metric=1024
 EOF