scsi: qla2xxx: Remove set but not used variable 'ptr_dma'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/scsi/qla2xxx/qla_iocb.c: In function 'qla24xx_els_dcmd2_iocb':
drivers/scsi/qla2xxx/qla_iocb.c:2644:13: warning:
variable 'ptr_dma' set but not used [-Wunused-but-set-variable]

Signed-off-by: YueHaibing <[e-mail]>
Acked-by: Himanshu Madhani <[e-mail]>
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/scsi/qla2xxx/qla_iocb.c

···
 	struct qla_hw_data *ha = vha->hw;
 	int rval = QLA_SUCCESS;
 	void	*ptr, *resp_ptr;
-	dma_addr_t ptr_dma;
 
 	/* Alloc SRB structure */
 	sp = qla2x00_get_sp(vha, fcport, GFP_KERNEL);
···
 	ptr = elsio->u.els_plogi.els_plogi_pyld =
 	    dma_alloc_coherent(&ha->pdev->dev, DMA_POOL_SIZE,
 		&elsio->u.els_plogi.els_plogi_pyld_dma, GFP_KERNEL);
-	ptr_dma = elsio->u.els_plogi.els_plogi_pyld_dma;
 
 	if (!elsio->u.els_plogi.els_plogi_pyld) {
 		rval = QLA_FUNCTION_FAILED;