cryptsetup-generator: allow whitespace characters in keydev specification
    
    For example, <luks.uuid>=/keyfile:LABEL="KEYFILE FS" previously wouldn't
    work, because we truncated label at the first whitespace character,
    i.e. LABEL="KEYFILE".
    
    (cherry-picked from commit 7949dfa73a44ae6524779689483d12243dfbcfdf)
    
    Related: #1656869
    
    patch_name: 0051-cryptsetup-generator-allow-whitespace-characters-in-.patch
    present_in_specfile: true
    location_in_specfile: 51
    squash_commits: true