filesystems: bump priority of BFS over others

If multipole filesystems think they can handle a volume, it makes sense
to assume the native one is to be used.

Makes my partitions with a BFS superblock and a leftover ext2 superblock
on them mountable again without manually specifying the filesystem type.

Fixes #15045.

Change-Id: Icb694472aa3de0a79e5f7d3c54976038e1e2590a
Reviewed-on: https://review.haiku-os.org/c/haiku/+/1801
Reviewed-by: waddlesplash <waddlesplash@gmail.com>

src/add-ons/kernel/file_systems/bfs/kernel_interface.cpp

@@ -134,7 +134,7 @@ bfs_identify_partition(int fd, partition_data* partition, void** _cookie)
 	memcpy(&cookie->super_block, &superBlock, sizeof(disk_super_block));
 
 	*_cookie = cookie;
-	return 0.8f;
+	return 0.85f;
 }