Add linux-dcheck-off-rel builder to buildbucket configuration.

Bug: 833482
Change-Id: I359fd5b64701fd9e960ad380231206e8b268efeb
Reviewed-on: https://chromium-review.googlesource.com/1116245
Commit-Queue: Garrett Beaty <gbeaty@chromium.org>
Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Reviewed-by: Ryan Tseng <hinoka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#573331}

infra/config/global/cr-buildbucket.cfg

@@ -2455,6 +2455,7 @@ buckets {
     builders { mixins: "linux-try" name: "linux-blink-gen-property-trees" }
     builders { mixins: "linux-try" name: "linux-blink-heap-incremental-marking" }
     builders { mixins: "linux-try" name: "linux-blink-heap-verification-try" }
+    builders { mixins: "linux-try" name: "linux-dcheck-off-rel" }
     builders { mixins: "linux-try" name: "linux-gcc-rel" }
     builders { mixins: "linux-try" name: "linux-jumbo-rel" }
     builders { mixins: "linux-try" name: "linux-ozone-rel" }