scsi: qla2xxx: Declare qla2xxx_mqueuecommand() static

scsi: qla2xxx: Declare qla2xxx_mqueuecommand() static

Prevent that a later patch that modifies the qla2xxx_mqueuecommand()
declaration triggers the following checkpatch warning: "externs should
be avoided in .c files".

Cc: Nilesh Javali <njavali@marvell.com>
Cc: GR-QLogic-Storage-Upstream@marvell.com
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Link: https://patch.msgid.link/20260115210357.2501991-5-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>