clk: meson: meson8b: Fix the polarity of the RESET_N lines

CLKC_RESET_VID_DIVIDER_CNTL_RESET_N_POST and
CLKC_RESET_VID_DIVIDER_CNTL_RESET_N_PRE are active low. This means:
- asserting them requires setting the register value to 0
- de-asserting them requires setting the register value to 1

Set the register value accordingly for these two reset lines by setting
the inverted the register value compared to all other reset lines.

Fixes: 18962172 ("clk: meson: meson8b: register the built-in reset controller")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20200417184127.1319871-3-martin.blumenstingl@googlemail.com