[SCSI] qla2xxx: Ignore payload reserved-bits during RSCN processing.

As the driver is only interested in bits 0-9 of the 1st
RSCN-payload word:

	rsvd[15:14]RscnEventQualifier[13:10]Fmt[9:8]Domain[7:0]
	Area[15:8]Alpa[7:0]

Signed-off-by: Ravi Anand <ravi.anand@qlogic.com>
Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>