Temporarily disable FreeBSD-12

...until the bugs in the google-compute-engine scripts are fixed
upstream.

Change-Id: I0426289b76d4c89a9a40ddd0a2d9ed96415eccb4
diff --git a/jenkins/BUILD b/jenkins/BUILD
index 5628011..4d29186 100644
--- a/jenkins/BUILD
+++ b/jenkins/BUILD
@@ -29,9 +29,6 @@
 FREEBSD_11_PREFIX = "freebsd-11"
 FREEBSD_11_COUNT = 2
 
-FREEBSD_12_PREFIX = "freebsd-12"
-FREEBSD_12_COUNT = 2
-
 UBUNTU_1404_PREFIX = "ubuntu_14.04-x86_64"
 UBUNTU_1404_COUNT = 4
 
@@ -88,12 +85,6 @@
     labels = ["no-release"],
 )
 
-jenkins_nodes(
-    FREEBSD_12_PREFIX,
-    FREEBSD_12_COUNT,
-    labels = ["no-release"],
-)
-
 #
 # A deploy slave used for release work and syncing
 # our repositories.
@@ -260,7 +251,6 @@
                   ":config/org.jenkinsci.plugins.ghprb.GhprbTrigger.xml",
               ] + jenkins_node_names(DARWIN_PREFIX, DARWIN_COUNT) +
               jenkins_node_names(FREEBSD_11_PREFIX, FREEBSD_11_COUNT) +
-              jenkins_node_names(FREEBSD_12_PREFIX, FREEBSD_12_COUNT) +
               jenkins_node_names(WINDOWS_PREFIX, WINDOWS_COUNT) +
               jenkins_node_names(UBUNTU_DOCKER_PREFIX, UBUNTU_DOCKER_COUNT) +
               jenkins_node_names(UBUNTU_1404_PREFIX, UBUNTU_1404_COUNT) +
@@ -283,7 +273,6 @@
         ":darwin-x86_64-staging",
         ":deploy-staging",
         ":freebsd-11-staging",
-        ":freebsd-12-staging",
         ":jenkins-common-configs",
         ":ubuntu_14.04-x86_64-staging",
         ":ubuntu_16.04-x86_64-docker-staging",