Allow picking different manifest based on boardName

- Excelsior's manifest currently lives elsewhere. Pick by board name.
- Add a rewrite rule for excelsior.

Change-Id: I7984bcdf22bbce5439c0f9574d65d20bd865e87a
diff --git a/vars/functions.groovy b/vars/functions.groovy
index ee41cf1..9e7ae84 100644
--- a/vars/functions.groovy
+++ b/vars/functions.groovy
@@ -5,17 +5,19 @@
        /opt/gcompute-tools/git-cookie-authdaemon
 
        git config --global url.https://aiyprojects.googlesource.com/.insteadOf sso://aiyprojects/
+       git config --global url.https://excelsior.googlesource.com/.insteadOf sso://excelsior/
 
        mkdir -p .repo/local_manifests
        mkdir -p cache
        chmod 777 cache .repo/local_manifests
        """
 
+
     timeout(time: 20, unit: 'MINUTES') {
         checkout([$class: 'RepoScm',
                   currentBranch: true,
                   jobs: 24,
-                  manifestRepositoryUrl: 'http://coral.googlesource.com/manifest',
+                  manifestRepositoryUrl: manifestUrlFromBoardName(boardName),
                   manifestBranch: 'master',
                   manifestFile: "${boardName}.xml",
                   manifestGroup: "default,internal",
@@ -41,6 +43,17 @@
     sh "bash -c 'source build/setup.sh; m -j${nprocs} prereqs ${targetName}; exit \$?'"
 }
 
+def manifestUrlFromBoardName(boardName) {
+    switch (boardName) {
+        case "excelsior":
+            return "http://aiyprojects.googlesource.com/manifest"
+        case "enterprise":
+            return "http://coral.googlesource.com/manifest"
+        default:
+            error "Unknown board ${boardName}"
+    }
+}
+
 def nameFromRepoType(repoType, boardName) {
     if (repoType == "core") {
         return "core"