Implement the sceRtc formatting and reincarnated time funcs

sceRtcGetLastAdjustedTime() no longer returns the current time, but rather a fixed time in the past (so it doesn't look like the user is fiddling with the clock.)  Not sure if this will actually improve anything.

sceRtcGetLastReincarnatedTime() also now returns a fixed time in the past.  This may help NPJH50333 or NPJH90154 (Yakuza and its demo), which have been reported calling it.

sceRtcFormatRFC*() now produce a valid string, whereas it might've been garbage before.  This may impact any of NPJH50426 (Taiko no Tatsujin Portable DX), UCUS98620 / UCES00006 (MediEvil Resurrection), UCES01531 / UCES01462 / UCUS98759 (EyePet Adventures), NPEH00002 / NPUH10007 (No Gravity), ULES00198 / ULES00199 / ULES00202 / ULUS10038 (Lord of the Rings Tactics), NPJH90201 (dunno?), NPJH50832 (God Eater 2), ULJS00108 (IQ Cube), UCKS45019 (Work Time Fun), which have been reported using it.

-[Unknown]