[view-compiler] Better namespacing of util functions

This moves some helper functions into our own namespace to avoid conflicting
with other util.h files.

Bug: 111895153
Change-Id: I2b4c77732a97b34a8528d69867c15ed802686703
diff --git a/startop/view_compiler/util.h b/startop/view_compiler/util.h
index 03e0939..0176175 100644
--- a/startop/view_compiler/util.h
+++ b/startop/view_compiler/util.h
@@ -13,11 +13,17 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-#ifndef UTIL_H_
-#define UTIL_H_
+#ifndef VIEW_COMPILER_UTIL_H_
+#define VIEW_COMPILER_UTIL_H_
 
 #include <string>
 
+namespace startop {
+namespace util {
+
 std::string FindLayoutNameFromFilename(const std::string& filename);
 
-#endif  // UTIL_H_
+}  // namespace util
+}  // namespace startop
+
+#endif  // VIEW_COMPILER_UTIL_H_