LJpegDecompressor::decodeN(): silence implicit conversion issue
LJpegDecompressor::decodeN(): silence implicit conversion issue

https://github.com/darktable-org/rawspeed/issues/175

darktable-org/rawspeed,LebedevRI/rawspeed,darktable-org/rawspeed,darktable-org/rawspeed,LebedevRI/rawspeed,LebedevRI/rawspeed,LebedevRI/rawspeed,LebedevRI/rawspeed,darktable-org/rawspeed,darktable-org/rawspeed