Without FLAG UTF-8, Hunspell reads a field that names one flag (PFX/SFX,
KEEPCASE, FORBIDDENWORD and the like) through decode_flag, which takes its
first byte: SFX é is the flag 0xC3. Such a field no longer fails the load.
SYLLABLENUM lists flags and is read byte by byte like AF. SET and FLAG
read only their first argument, so FLAG UTF-8 with a trailing comment
keeps Unicode flags.