usb: host: u132-hcd: Remove u132_static_list and list head u132_list

u132_static_list is a global list protected by u132_module_lock.
It is read in the u132_hcd_exit() function without holding the lock
thus may lead to data race.
However, it turns out that this list isn't used for anything useful
and thus it is okay to get rid of it.
Thus, remove the u132_static_list from u132-hcd module.
Also remove struct list_head u132_list from struct u132.

Found by Linux Driver Verification project (linuxtesting.org).

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Link: https://lore.kernel.org/r/20200404174102.19862-1-madhuparnabhowmik10@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>