qsd: Document fuse's allow-other option

We did not add documentation to the storage daemon's man page for fuse's
allow-other option when it was introduced, so do that now.

Fixes: 8fc54f9428b9763f800 ("export/fuse: Add allow-other option")
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220131103124.20325-1-hreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/storage-daemon/qemu-storage-daemon.c b/storage-daemon/qemu-storage-daemon.c
index ec9aa79..504d33a 100644
--- a/storage-daemon/qemu-storage-daemon.c
+++ b/storage-daemon/qemu-storage-daemon.c
@@ -100,7 +100,7 @@
 "\n"
 #ifdef CONFIG_FUSE
 "  --export [type=]fuse,id=<id>,node-name=<node-name>,mountpoint=<file>\n"
-"           [,growable=on|off][,writable=on|off]\n"
+"           [,growable=on|off][,writable=on|off][,allow-other=on|off|auto]\n"
 "                         export the specified block node over FUSE\n"
 "\n"
 #endif /* CONFIG_FUSE */