clk: sunxi: Add apb0 gates for A83T

APB0 is part of PRCM, and is compatible with earlier SOCs.
apb0 gates controls R_PIO, R_UART, R_RSB, etc clocks.
This patch adds support for APB0 gates for A83T.

Signed-off-by: Vishnu Patekar <vishnupatekar0510@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>