toolchain: Add kahlee board to nightly llvm tests.

Kahlee is a new board using AMD stoney ridge platform.

BUG=None
TEST=Kahlee-llvm-toolchain-tryjob job is created.

Change-Id: I2c04c482d63ba2bc1cb79ded4402a69618b4f2dc
Reviewed-on: https://chromium-review.googlesource.com/869171
Commit-Ready: Manoj Gupta <manojgupta@chromium.org>
Tested-by: Manoj Gupta <manojgupta@chromium.org>
Reviewed-by: Luis Lozano <llozano@chromium.org>
diff --git a/buildbot_test_llvm.py b/buildbot_test_llvm.py
index 6c39c3a..5401b61 100755
--- a/buildbot_test_llvm.py
+++ b/buildbot_test_llvm.py
@@ -43,6 +43,7 @@
 #  daisy      armv7    daisy      exynos-5250   3.8.11
 #  eve        x86_64   poppy      kabylake-y    4.4.79
 #  gale       armv7                             3.18
+#  kahlee     x86_64   kahlee     stoney ridge  4.14
 #  kevin      armv7    gru        rockchip-3399 4.4.79
 #  lakitu     x86_64                            4.4.79
 #  link       x86_64   ivybridge  ivybridge     3.8.11
@@ -61,6 +62,7 @@
     'daisy',
     'eve',
     'gale',
+    'kahlee',
     'kevin',
     'lakitu',
     'link',