Minor changes to cdvdGigaherz

Just some minor changes for readability.

Also, I'd like to point out line 143 and 147 of TocStuff.cpp. They both assign `CDVD_MODE1_TRACK`. I believe one of them should have originally been `CDVD_MODE2_TRACK`. Though I'm not sure which one, which is why I have left it for now.