This replaces Wine's 10 copies of the function.
-- v2: strmbase: Use debugstr_reftime instead of reimplementing it. wmvcore: Use debugstr_reftime instead of reimplementing it. winegstreamer: Use debugstr_reftime instead of reimplementing it. quartz: Use debugstr_reftime instead of reimplementing it. qasf: Use debugstr_reftime instead of reimplementing it. mfsrcsnk: Use debugstr_reftime instead of reimplementing it. mfplat: Use debugstr_reftime instead of reimplementing it. mf: Use debugstr_reftime instead of reimplementing it. evr: Use debugstr_reftime instead of reimplementing it. include: Introduce debugstr_reftime and wine_dbgstr_reftime.