Fixup bug in PMIC TPS65217 register address definition

The addresses of the registers in TI TPS65217 are not continuous.
     There is a gap between ENABLE(0x16) and DEFUVLO(0x18). No 0x17
     register available.

     Fixup the enum values by adding a 'reserved' placeholder to correct
     the addresses higher than 0x17.

     Series-to: Heiko Schocher <hs@denx.de>

Signed-off-by: Brock Zheng Techyauld Ltd <yzheng@techyauld.com>
Reviewed-by: Lukasz Majewski <lukma@denx.de>