Remove duplicate format functions (#738)

This moves the filter_formats and get_format_list functions to a common
file. These functions were roughly the same, with an optional filtering
in some tests for testing mipmaps.

Signed-off-by: Radek Szymanski <radek.szymanski@arm.com>

test_conformance/images/common.h

@@ -0,0 +1,34 @@
+//
+// Copyright (c) 2020 The Khronos Group Inc.
+//
+// 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.
+//
+#ifndef IMAGES_COMMON_H
+#define IMAGES_COMMON_H
+
+#include "harness/kernelHelpers.h"
+#include "harness/errorHelpers.h"
+
+extern cl_channel_type gChannelTypeToUse;
+extern cl_channel_order gChannelOrderToUse;
+
+const char *convert_image_type_to_string(cl_mem_object_type imageType);
+int filter_formats(cl_image_format *formatList, bool *filterFlags,
+                   unsigned int formatCount,
+                   cl_channel_type *channelDataTypesToFilter,
+                   bool testMipmaps = false);
+int get_format_list(cl_context context, cl_mem_object_type imageType,
+                    cl_image_format *&outFormatList,
+                    unsigned int &outFormatCount, cl_mem_flags flags);
+
+#endif // IMAGES_COMMON_H