multipath-tools: make HUAWEI/XSG1 config work with alua and multibus

And add recommended no_path_retry and pgfailback values.

Info from:
- RHEL https://download.huawei.com/edownload/e/download.do?actionFlag=download&nid=EDOC1100113070&partNo=6001&mid=SUPE_DOC&_t=1612885511000
- SLES https://download.huawei.com/edownload/e/download.do?actionFlag=download&nid=EDOC1100117892&partNo=6001&mid=SUPE_DOC&_t=1612885538000

- without HyperMetro:
vendor "HUAWEI"
product "XSG1"
path_grouping_policy multibus
no_path_retry 15

- with HyperMetro:
vendor "HUAWEI"
product "XSG1"
path_grouping_policy group_by_prio
prio alua
failback immediate
no_path_retry 15

ALUA is only used with HyperMetro(cluster of two arrays).

Suggested-by: Martin Wilck <mwilck@suse.com>
Cc: Zhouweigang (Jack) <zhouweigang09@huawei.com>
Cc: Zou Ming <zouming.zouming@huawei.com>
Cc: Benjamin Marzinski <bmarzins@redhat.com>
Cc: Martin Wilck <mwilck@suse.com>
Cc: Christophe Varoqui <christophe.varoqui@opensvc.com>
Cc: DM-DEVEL ML <dm-devel@redhat.com>
Signed-off-by: Xose Vazquez Perez <xose.vazquez@gmail.com>
Reviewed-by: Martin Wilck <mwilck@suse.com>"

libmultipath/hwtable.c

@@ -1078,11 +1078,14 @@ static struct hwentry default_hw[] = {
 	 * Huawei
 	 */
 	{
-		/* OceanStor V3 */
+		/* OceanStor V3-V6 */
+		// This config works with multibus and ALUA
+		// ALUA is required by HyperMetro
 		.vendor        = "HUAWEI",
 		.product       = "XSG1",
 		.pgpolicy      = GROUP_BY_PRIO,
-		.prio_name     = PRIO_ALUA,
+		.pgfailback    = -FAILBACK_IMMEDIATE,
+		.no_path_retry = 15,
 	},
 	/*
 	 * Kove