Coverity: fix UNINIT in RawImageDataU16::fixBadPixel
Coverity: fix UNINIT in RawImageDataU16::fixBadPixel

CID 1025898

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