[SCSI] libfc: Do not retry if the new state is not the same as old state

For instance, if there is a Plogi pending (remote port is in Plogi state),
and the state changes to say NONE (because the port is being logged off),
then when the Plogi resp times out, do not start a retry.

This patch partially reverts an earlier patch (libfc: check for err when
recv and state is incorrect), by moving the state check back to before
checking for error. However, if the state does not match, then there is
an additional check to see if its an error ptr or a real frame before
jumping to err or out respectively.

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>