milo: Remove remaining references to chromium.linux buildbots.

Bug: 840218
Change-Id: Ibe0f94184c636d93847f036e5ae65b9efa9d9213
Reviewed-on: https://chromium-review.googlesource.com/1047847
Reviewed-by: Ryan Tseng <hinoka@chromium.org>
Commit-Queue: John Budorick <jbudorick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#556492}

infra/config/global/luci-milo.cfg

@@ -435,19 +435,16 @@ consoles: {
     short_name: "det"
   }
   builders: {
-    name: "buildbot/chromium.linux/Leak Detection Linux"
     name: "buildbucket/luci.chromium.ci/Leak Detection Linux"
     category: "chromium.linux"
     short_name: "lk"
   }
   builders: {
-    name: "buildbot/chromium.linux/Cast Linux"
     name: "buildbucket/luci.chromium.ci/Cast Linux"
     category: "chromium.linux|cast"
     short_name: "vid"
   }
   builders: {
-    name: "buildbot/chromium.linux/Cast Audio Linux"
     name: "buildbucket/luci.chromium.ci/Cast Audio Linux"
     category: "chromium.linux|cast"
     short_name: "aud"
@@ -869,7 +866,6 @@ consoles: {
   header_id: "chromium"
 
   builders: {
-    name: "buildbot/chromium.linux/Linux Builder"
     name: "buildbucket/luci.chromium.ci/Linux Builder"
     category: "release"
     short_name: "bld"
@@ -895,7 +891,6 @@ consoles: {
     short_name: "32"
   }
   builders: {
-    name: "buildbot/chromium.linux/Linux Builder (dbg)"
     name: "buildbucket/luci.chromium.ci/Linux Builder (dbg)"
     category: "debug|builder"
     short_name: "64"
@@ -915,18 +910,15 @@ consoles: {
     short_name: "det"
   }
   builders: {
-    name: "buildbot/chromium.linux/Leak Detection Linux"
     name: "buildbucket/luci.chromium.ci/Leak Detection Linux"
     short_name: "lk"
   }
   builders: {
-    name: "buildbot/chromium.linux/Cast Linux"
     name: "buildbucket/luci.chromium.ci/Cast Linux"
     category: "cast"
     short_name: "lnx"
   }
   builders: {
-    name: "buildbot/chromium.linux/Cast Audio Linux"
     name: "buildbucket/luci.chromium.ci/Cast Audio Linux"
     category: "cast"
     short_name: "aud"
@@ -1465,28 +1457,6 @@ consoles: {
   header_id: "chromium"
   include_experimental_builds: true
 
-  builders {
-    name: "buildbucket/luci.chromium.ci/Cast Audio Linux"
-    category: "linux|cast|audio"
-    short_name: "ci"
-  }
-  builders {
-    name: "buildbot/chromium.linux/Cast Audio Linux"
-    category: "linux|cast|audio"
-    short_name: "bb"
-  }
-
-  builders {
-    name: "buildbucket/luci.chromium.ci/Leak Detection Linux"
-    category: "linux|leak"
-    short_name: "ci"
-  }
-  builders {
-    name: "buildbot/chromium.linux/Leak Detection Linux"
-    category: "linux|leak"
-    short_name: "bb"
-  }
-
   builders: {
     name: "buildbucket/luci.chromium.ci/Win Builder"
     category: "win|release|builder|32"