TESTS: move the default url, lun and iscsi context into a structure

Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>

test-tool/test_unmap_vpd.c

@@ -40,7 +40,7 @@ test_unmap_vpd(void)
 	logging(LOG_VERBOSE, "Check if UNMAP is available.");
 	list[0].lba = 0;
 	list[0].num = 0;
-	ret = unmap(iscsic, tgt_lun, 0, list, 1,
+	ret = unmap(sd->iscsi_ctx, sd->iscsi_lun, 0, list, 1,
 		    EXPECT_STATUS_GOOD);
 	if (ret != 0) {
 		logging(LOG_VERBOSE, "UNMAP is not available. Verify that VPD "