utils: Pass lock argument in fileslocked
    
    Pass additional arguments in the fileslocked() context manager to the
    underlying lockfile() function. This allows the context manager to be
    used for any types of locks (non-blocking, shared, etc.) that the
    lockfile() function supports.
    
    Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
    Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>