This has qla4xxx use the iscsi class's check ready function
in the queue command function, so all iscsi drivers return the
same error value for common problems.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Cc: David Somayajulu <david.somayajulu@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>