[SCSI] libsas: Clean up rphys/port dev list after a discovery error on an expander

[SCSI] libsas: Clean up rphys/port dev list after a discovery error on an expander

sas_get_port_device assigns a rphy to a domain device in anticipation
of finding a disk.  When a discovery error occurs in
sas_discover_{sata,sas,expander}*, however, we need to clean up that
rphy and the port device list so that we don't GPF.  In addition, we
need to check the result of the second sas_notify_lldd_dev_found.
This patch seems ok on a x260, x366 and x206m.

This patch fixes up sas_expander.c separately because jejb has some
cleanup patches of his own that are a prerequisite.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>