Try fixing sceJpegGetOutputInfo again

I guess the colour info address isn't supposed to be updated if the jpeg errors out, or I think so based on reports from the God Eater Burst thread in the forums. This shouldn't affect working jpegs since the address is still being updated before returning, just not if it errors out. If this doesn't work for the save from the forums, it would have never worked in PPSSPP builds up to today (it basically makes the function _only_ return null without updating the colour address, making it the equivalent of the only implementation other than mine, which was a stub, if it errors out). The previous commit I made worked in the Japanese version, but still bounced back in the US version (wtf?).
Merge pull request #3088 from CPkmn/patch-2

Try fixing sceJpegGetOutputInfo again