[ATM]: Use mutex instead of binary semaphore in idt77252 driver.

Use mutex instead of binary semaphore in idt77252 driver.

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>