Remove skip_bazel_to_cmake marker file support. (#4931)

* All of the BUILD files it was guarding no longer exist.
diff --git a/bindings/python/pyiree/compiler2/.skip_bazel_to_cmake b/bindings/python/pyiree/compiler2/.skip_bazel_to_cmake
deleted file mode 100644
index e69de29..0000000
--- a/bindings/python/pyiree/compiler2/.skip_bazel_to_cmake
+++ /dev/null
diff --git a/bindings/python/pyiree/jax/.skip_bazel_to_cmake b/bindings/python/pyiree/jax/.skip_bazel_to_cmake
deleted file mode 100644
index e69de29..0000000
--- a/bindings/python/pyiree/jax/.skip_bazel_to_cmake
+++ /dev/null
diff --git a/bindings/python/pyiree/rt/.skip_bazel_to_cmake b/bindings/python/pyiree/rt/.skip_bazel_to_cmake
deleted file mode 100644
index e69de29..0000000
--- a/bindings/python/pyiree/rt/.skip_bazel_to_cmake
+++ /dev/null
diff --git a/bindings/python/pyiree/tools/core/.skip_bazel_to_cmake b/bindings/python/pyiree/tools/core/.skip_bazel_to_cmake
deleted file mode 100644
index e69de29..0000000
--- a/bindings/python/pyiree/tools/core/.skip_bazel_to_cmake
+++ /dev/null
diff --git a/bindings/python/tests/.skip_bazel_to_cmake b/bindings/python/tests/.skip_bazel_to_cmake
deleted file mode 100644
index e69de29..0000000
--- a/bindings/python/tests/.skip_bazel_to_cmake
+++ /dev/null
diff --git a/build_tools/bazel_to_cmake/bazel_to_cmake.py b/build_tools/bazel_to_cmake/bazel_to_cmake.py
index 15dc6ba..0d8beb5 100755
--- a/build_tools/bazel_to_cmake/bazel_to_cmake.py
+++ b/build_tools/bazel_to_cmake/bazel_to_cmake.py
@@ -151,15 +151,12 @@
   if verbosity >= 1:
     log(f"Processing {rel_dir_path}")
 
-  skip_file_path = os.path.join(directory_path, ".skip_bazel_to_cmake")
   build_file_path = os.path.join(directory_path, "BUILD")
   cmakelists_file_path = os.path.join(directory_path, "CMakeLists.txt")
 
   rel_cmakelists_file_path = repo_relpath(cmakelists_file_path)
   rel_build_file_path = repo_relpath(build_file_path)
 
-  if os.path.isfile(skip_file_path):
-    return Status.SKIPPED
   if not os.path.isfile(build_file_path):
     return Status.NO_BUILD_FILE
 
diff --git a/integrations/tensorflow/bindings/python/pyiree/tools/tf/.skip_bazel_to_cmake b/integrations/tensorflow/bindings/python/pyiree/tools/tf/.skip_bazel_to_cmake
deleted file mode 100644
index e69de29..0000000
--- a/integrations/tensorflow/bindings/python/pyiree/tools/tf/.skip_bazel_to_cmake
+++ /dev/null