(U-000248AA): Use `->denotational' and `->subsumptive'; add
`<-denotational' for A-IWDSU+7375.
(M-20759): Unify MJ040896, KOSEKI-232950, S1-4812 and S2-4814.
(U+7375): Apply new conventions for glyph granularity; add
`<-denotational' for A-IWDSU+7375.
(S2-4814): Unify IU+248AA.