fc_transport: The softirq_done function registration for BSG request

Registered the softirq_done function, since this is requried iby an request
using block level request timeout functionality. This function will be called
by the block layer as part of time out clean process to release the BSG
request.

Moved some of the BSG request completion activities to softirq_done routine to
take care of both normal and timout completions.

Signed-off-by: Giridhar Malavali <giridhar.malavali@qlogic.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>