ios build fix on xcode version < 10.0
ios build fix on xcode version < 10.0

(unknown clang warning)

Buddy: Sam

wrld3d/wrld-example-app,wrld3d/wrld-example-app,wrld3d/wrld-example-app,eegeo/eegeo-example-app,eegeo/eegeo-example-app,eegeo/eegeo-example-app,wrld3d/wrld-example-app,eegeo/eegeo-example-app,eegeo/eegeo-example-app,eegeo/eegeo-example-app,wrld3d/wrld-example-app,wrld3d/wrld-example-app,wrld3d/wrld-example-app,wrld3d/wrld-example-app,eegeo/eegeo-example-app