basic: remove an assertion from cunescape_one
    
    The function takes a pointer to a random block of memory and
    the length of that block. It shouldn't crash every time it sees
    a zero byte at the beginning there.
    
    This should help the dev-kmsg fuzzer to keep going.
    
    (cherry picked from commit 8dc4de966ce6d32470aaff30ed054f6a2688d6d7)
    
    Resolves: #1764560
    
    patch_name: 0254-basic-remove-an-assertion-from-cunescape_one.patch
    present_in_specfile: true
    location_in_specfile: 254
    squash_commits: true