scsi: megaraid_sas: reduce size of fusion_context and use vmalloc if kmalloc fails

scsi: megaraid_sas: reduce size of fusion_context and use vmalloc if kmalloc fails

Orabug: 26096381

Currently fusion context has fixed array load_balance_info. Use dynamic
allocation.  In few places, driver do not want physically contigious
memory.  Attempt to use vmalloc if physical contiguous memory is not
available.

Signed-off-by: Shivasharan S <shivasharan.srikanteshwara@broadcom.com>
Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
(cherry picked from commit 5fc499b612c5401a7ae0674086befcdf8b148516)
Signed-off-by: Somasundaram Krishnasamy <somasundaram.krishnasamy@oracle.com>
Signed-off-by: Kirtikar Kashyap <kirtikar.kashyap@oracle.com>
Reviewed-by: Dhaval Giani <dhaval.giani@oracle.com>
Conflicts:
	drivers/scsi/megaraid/megaraid_sas.h