OMAP2+: PM: Fix the saving of CM_AUTOIDLE_PLL register on scratchpad area

The saving of CCR.CM_AUTOIDLE_PLL is done in scratchpad area.

However, in current code, the saving is done for CM_AUTOIDLE2_PLL
(offset 0x34) instead of CM_AUTOIDLE_PLL (offset 0x30).

This patch changes the code to save the correct register.

Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>