[SCSI] mpt fusion: Avoid racing when mptsas and mptcl module are loaded in parallel

This patch sets the IOC pointer in drvrdata of pcidev before adding
the IOC into the list of IOCs. Without this patch the driver oops when
the mptsas and mptctl modules are loaded in parallel.

Signed-off-by: Sathya Prakash <sathya.prakash@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>