MLK-11550-1: regulator: pfuze100: restore some registers after LPSR for pfuze3000

MLK-11550-1: regulator: pfuze100: restore some registers after LPSR for pfuze3000

Some registers on pfuze3000 will lost after exit from LPSR, need restore them,
otherwise system may reboot with below command after system enter LPSR one time:

root@imx7d_all:~# echo enabled > /sys/class/tty/ttymxc0/power/wakeup
root@imx7d_all:~# echo mem > /sys/power/state

because LDOGCTL not recover as 1. Add 'fsl,lpsr-mode' property to this case,
please add this property if your board support LPSR mode as imx7d-12x12-lpddr3-arm2
board.

Signed-off-by: Robin Gong <b38343@freescale.com>