[SCSI] hpsa: combine hpsa_scsi_detect and hpsa_register_scsi

hpsa_register_scsi just calls hpsa_scsi_detect.  Move
the guts of hpsa_scsi_detect into hpsa_register_scsi and
get rid of hpsa_scsi_detect.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>