clk: vc5: Check IO access results

The devices of the versaclk clock generator family use an I2C control bus.
IO access on an I2C bus can fail for various reasons.

The driver currently ignores the return value of most IO operations. This
results in silent failure. To avoid this check the return value and in case
of an error abort the operation and propagate the error code to the caller.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20220719094637.844946-1-lars@metafoo.de


Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>