[WIP] Histogram CPU

Signed-off-by: Piotr Rak <prak@nvidia.com>

Author: prak-nv

dali/operators/generic/CMakeLists.txt

@@ -15,6 +15,7 @@
 # Get all the source files and dump test files
 
 add_subdirectory(erase)
+add_subdirectory(histogram)
 add_subdirectory(reduce)
 add_subdirectory(slice)
 add_subdirectory(transpose)

dali/operators/generic/histogram/CMakeLists.txt

@@ -0,0 +1,18 @@
+# Copyright (c) 2019, NVIDIA CORPORATION. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Get all the source files and dump test files
+collect_headers(DALI_INST_HDRS PARENT_SCOPE)
+collect_sources(DALI_OPERATOR_SRCS PARENT_SCOPE)
+collect_test_sources(DALI_OPERATOR_TEST_SRCS PARENT_SCOPE)