iio: common: scmi_iio: Remove unnecessary u64 type cast

The variable uHz already has the type u64 and casting it to u64 is
unnecessary. Remove the redundant type cast.

Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Link: https://patch.msgid.link/20240711134502.168484-1-thorsten.blum@toblux.com


Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>