[SCSI] mpt2sas: Fix for panic happening because of improper memory allocation

The ioc->pfacts member in the IOC structure is getting set to zero
following a call to _base_get_ioc_facts due to the memset in that routine.
So if the ioc->pfacts was read after a host reset, there would be a NULL
pointer dereference. The routine _base_get_ioc_facts is called from context
of host reset.  The problem in _base_get_ioc_facts  is the size of
Mpi2IOCFactsReply is 64, whereas the sizeof "struct mpt2sas_facts" is 60,
so there is a four byte overflow resulting from the memset.

Also, there is memset in _base_get_port_facts using the incorrect structure,
it should be "struct mpt2sas_port_facts" instead of Mpi2PortFactsReply.

Signed-off-by: Nagalakshmi Nandigama <nagalakshmi.nandigama@lsi.com>
CC: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>