Changes

icE1usb fw: Avoid casting random pointer to struct in set_{rx,tx}_mode

There is really no need here, we can use `memcpy` just as well.

Not sure if this was a problem here but newer gcc are annoying
with aliasing rules and such so better safe than sorry.

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Change-Id: I110ee4c014e8cfe058f7fc357decb7ab99e0be64