Detect bad fonts ascenders and workaround

Fixes #4765 with the fonts that come with PPSSPP.

There was already code to do this, `isJPCSPFont()`, it just wasn't firing properly.

Since this also corrects the horizontal adjust, it broke FF3 again, due to the "packedFont" hack, so I removed it.  The values should be right now (and I believe they're also per character.)

-[Unknown]