allwinner: Use RSB for the PMIC connection on H6

RSB is faster and more efficient, and it has a simpler driver. As long
as the PMIC is returned to I2C mode after use, the rich OS can later use
either bus.

Change-Id: I0c5f32e88a090c8c5cccb81bd24596b301ab9da7
Signed-off-by: Samuel Holland <samuel@sholland.org>
4 files changed