wifi: mac80211_hwsim: use 32-bit skb cookie

commit cc5250cdb43d444061412df7fae72d2b4acbdf97 upstream.

We won't really have enough skbs to need a 64-bit cookie,
and on 32-bit platforms storing the 64-bit cookie into the
void *rate_driver_data doesn't work anyway. Switch back to
using just a 32-bit cookie and uintptr_t for the type to
avoid compiler warnings about all this.

Fixes: 4ee186fa7e40 ("wifi: mac80211_hwsim: fix race condition in pending packet")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Cc: Jeongik Cha <jeongik@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>