locking/rwsem: Remove an unused parameter of rwsem_wake()

The 2nd parameter 'count' is not used in this function.
The places where the function is called are also modified.

Signed-off-by: xuyehan <xuyehan@xiaomi.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lore.kernel.org/r/1625547043-28103-1-git-send-email-yehanxu1@gmail.com