bna: Serialize smem access during adapter initialization

Use init semaphore to serialize execution of the "unlock IOC semaphore"
code. Added bfa_ioc_fwver_clear() function to clear the firmware header if
last firmwar boot is not from driver.

Signed-off-by: Jing Huang <huangj@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>