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>

.gitignore

@@ -12,9 +12,7 @@ rust/target
 
 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

util/bot/DEPS

@@ -56,34 +56,11 @@ deps = {
     'dep_type': 'cipd',
   },
 
-  # TODO(davidben): Merge the three CMake directories. Now that we use CIPD,
-  # which supports a ${{platform}} marker, there is nothing platform-specific
-  # about this anymore. However, the recipe still expects CMake to be found at
-  # these directories, so this needs to be coordinated with a change there.
-  'boringssl/util/bot/cmake-linux64': {
+  'boringssl/util/bot/cmake': {
     'packages': [{
       'package': 'infra/3pp/tools/cmake/${{platform}}',
       'version': Var('cmake_version'),
     }],
-    'condition': 'host_os == "linux"',
-    'dep_type': 'cipd',
-  },
-
-  'boringssl/util/bot/cmake-mac': {
-    'packages': [{
-      'package': 'infra/3pp/tools/cmake/${{platform}}',
-      'version': Var('cmake_version'),
-    }],
-    'condition': 'host_os == "mac"',
-    'dep_type': 'cipd',
-  },
-
-  'boringssl/util/bot/cmake-win32': {
-    'packages': [{
-      'package': 'infra/3pp/tools/cmake/${{platform}}',
-      'version': Var('cmake_version'),
-    }],
-    'condition': 'host_os == "win"',
     'dep_type': 'cipd',
   },