Fix a compilation warning
Fix a compilation warning

caymard/openMVG,yoshidaken/openMVG,danylaksono/openMVG,Smozeley/openMVG,mojovski/openMVG,poparteu/openMVG,caymard/openMVG,poparteu/openMVG,Vinzza/openMVG,danylaksono/openMVG,yoshidaken/openMVG,poparteu/openMVG,danylaksono/openMVG,Vinzza/openMVG,openMVG/openMVG,yoshidaken/openMVG,Smozeley/openMVG,Vinzza/openMVG,caymard/openMVG,openMVG/openMVG,mojovski/openMVG,mojovski/openMVG,poparteu/openMVG,openMVG/openMVG,openMVG/openMVG,Smozeley/openMVG,openMVG/openMVG