iio: adc: cc10001: Use devm_clk_get_enabled() to avoid boilerplate.

As this driver just enables clock in probe() and disables in remove()
we can use this new function to replace boilerplate and simplify
error paths.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20221016170950.387751-4-jic23@kernel.org