Fixed KIO::suggestName to suggest correct names

Earlier for filenames like filename-1.6.tar.gz, KIO::suggestName was
suggesting wrong names (filename-1 2.6.tar.gz, filename-1 3.6.tar.gz).
Now it suggests filename-1.6 (1).tar.gz for above given filename.

REVIEW: 123224
BUG: 341773