scsi: aacraid: Refactor resolve luns code and scsi functions

Resolve luns checks the if a sdev is already present in the os to figure
out if it needs to be removed. Internally the driver exposes HBA on bus
2 even though its bus 1 in the fw. Its mildly confusing.

Refactor out the sdev lookup into its function to check if sdev has been
added to the kernel or not. Add helper functions to add, remove and put
devices based on their fw bus and target number.

Signed-off-by: Raghava Aditya Renukunta <RaghavaAditya.Renukunta@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>