Use the common location for CMake in the bots

Follow-up to
https://chromium-review.googlesource.com/c/chromium/tools/build/+/4296194/

But mostly I've since added a lot more configurations to CI and want to
make sure I haven't broken anything.

Change-Id: I627711356004bf2244bd729b6055e9e0e619724e
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/57691
Commit-Queue: Bob Beck <bbe@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
diff --git a/.gitignore b/.gitignore
index a65880d..68dca6c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,9 +12,7 @@
 
 util/bot/android_ndk
 util/bot/android_sdk/public
-util/bot/cmake-linux64
-util/bot/cmake-mac
-util/bot/cmake-win32
+util/bot/cmake
 util/bot/golang
 util/bot/libFuzzer
 util/bot/libcxx