[clang-format] Add 'cl' to enable OpenCL kernel file formatting (#134529)

There are many .cl files in llvm repo. It would be great that
clang-format can support it.

NOKEYCHECK=True
GitOrigin-RevId: 923da2b843c7ddf9c7d39ba9629ad7945a96ea5c
diff --git a/git-clang-format b/git-clang-format
index 85eff47..b81077a 100755
--- a/git-clang-format
+++ b/git-clang-format
@@ -106,6 +106,7 @@
             "c++m",  # C++ Modules
             "cu",
             "cuh",  # CUDA
+            "cl",  # OpenCL
             # Other languages that clang-format supports
             "proto",
             "protodevel",  # Protocol Buffers