block: aoe: fixup coccinelle warnings

coccicheck complains about the use of snprintf() in sysfs show
functions:
WARNING  use scnprintf or sprintf

Use sysfs_emit instead of scnprintf or sprintf makes more sense.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Ye Guojin <ye.guojin@zte.com.cn>
Link: https://lore.kernel.org/r/20211021064931.1047687-1-ye.guojin@zte.com.cnSigned-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/aoe/aoeblk.c

@@ -37,8 +37,7 @@ static ssize_t aoedisk_show_state(struct device *dev,
 	struct gendisk *disk = dev_to_disk(dev);
 	struct aoedev *d = disk->private_data;
 
-	return snprintf(page, PAGE_SIZE,
-			"%s%s\n",
+	return sysfs_emit(page, "%s%s\n",
 			(d->flags & DEVFL_UP) ? "up" : "down",
 			(d->flags & DEVFL_KICKME) ? ",kickme" :
 			(d->nopen && !(d->flags & DEVFL_UP)) ? ",closewait" : "");
@@ -52,8 +51,8 @@ static ssize_t aoedisk_show_mac(struct device *dev,
 	struct aoetgt *t = d->targets[0];
 
 	if (t == NULL)
-		return snprintf(page, PAGE_SIZE, "none\n");
-	return snprintf(page, PAGE_SIZE, "%pm\n", t->addr);
+		return sysfs_emit(page, "none\n");
+	return sysfs_emit(page, "%pm\n", t->addr);
 }
 static ssize_t aoedisk_show_netif(struct device *dev,
 				  struct device_attribute *attr, char *page)
@@ -85,7 +84,7 @@ static ssize_t aoedisk_show_netif(struct device *dev,
 	ne = nd;
 	nd = nds;
 	if (*nd == NULL)
-		return snprintf(page, PAGE_SIZE, "none\n");
+		return sysfs_emit(page, "none\n");
 	for (p = page; nd < ne; nd++)
 		p += scnprintf(p, PAGE_SIZE - (p-page), "%s%s",
 			p == page ? "" : ",", (*nd)->name);
@@ -99,7 +98,7 @@ static ssize_t aoedisk_show_fwver(struct device *dev,
 	struct gendisk *disk = dev_to_disk(dev);
 	struct aoedev *d = disk->private_data;
 
-	return snprintf(page, PAGE_SIZE, "0x%04x\n", (unsigned int) d->fw_ver);
+	return sysfs_emit(page, "0x%04x\n", (unsigned int) d->fw_ver);
 }
 static ssize_t aoedisk_show_payload(struct device *dev,
 				    struct device_attribute *attr, char *page)
@@ -107,7 +106,7 @@ static ssize_t aoedisk_show_payload(struct device *dev,
 	struct gendisk *disk = dev_to_disk(dev);
 	struct aoedev *d = disk->private_data;
 
-	return snprintf(page, PAGE_SIZE, "%lu\n", d->maxbcnt);
+	return sysfs_emit(page, "%lu\n", d->maxbcnt);
 }
 
 static int aoedisk_debugfs_show(struct seq_file *s, void *ignored)