Refresh
    patches.suse/btrfs-reduce-contention-on-log-trees-when-logging-ch.patch.
    
    This fixes the following compilation warning:
    
    ../fs/btrfs/tree-log.c: In function 'log_extent_csums':
    ../fs/btrfs/tree-log.c:4177:4: warning: passing argument 1 of 'BTRFS_I' from incompatible pointer type [enabled by default]
    
    This happened after a merge from SLE15-SP1 into SLE12-SP5, and the warning
    is exclusive to SLE12-SP5, due to differences in the btrfs code between
    the two branches.