Fixed MinGW compile.
Fixed MinGW compile.

mgehre/rawspeed,darktable-org/rawspeed,anarsoul/rawspeed,LebedevRI/rawspeed,darktable-org/rawspeed,LebedevRI/rawspeed,darktable-org/rawspeed,LebedevRI/rawspeed,anarsoul/rawspeed,anarsoul/rawspeed,mgehre/rawspeed,LebedevRI/rawspeed,klauspost/rawspeed,LebedevRI/rawspeed,klauspost/rawspeed,darktable-org/rawspeed,darktable-org/rawspeed