Rename files for consistency (#1166)

Signed-off-by: Marco Antognini <marco.antognini@arm.com>

test_conformance/math_brute_force/sleep.h

@@ -0,0 +1,22 @@
+//
+// Copyright (c) 2017 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 SLEEP_H
+#define SLEEP_H
+
+void PreventSleep(void);
+void ResumeSleep(void);
+
+#endif /* SLEEP_H */