Implement meson_split_limit for meson

[ordinarymath]

HOL/src/meson/src/mesonLib.sml

Lines 778 to 779 in 7895c3c

	REPEAT(FIRST_X_ASSUM
	((DISJ_CASES_THEN ORELSE_TCL CONJUNCTS_THEN) ASSUME_TAC)) THEN

This needs to be done like

Meson.SPLIT_TAC (!meson_split_limit) THEN

  let rec SPLIT_TAC n g =
    ((FIRST_X_ASSUM(CONJUNCTS_THEN' ASSUME_TAC) THEN SPLIT_TAC n) ORELSE
     (if n > 0 then FIRST_X_ASSUM DISJ_CASES_TAC THEN SPLIT_TAC (n - 1)
      else NO_TAC) ORELSE
     ALL_TAC) g

see https://github.com/jrh13/hol-light/blob/2a1cea8f1cb7f3885a60d947ba06eabac6ec1d32/meson.ml