Here the compositor for the 1874 RLDS edition set way rather than away. Elsewhere the text has ten instances of “to be done away”. The expression “to be done way” is probably impossible for the Book of Mormon text, although dialectally the reduced way does occur as a variant for away (see the introductory discussion under away in the Oxford English Dictionary). The 1892 RLDS edition restored the obviously correct “to be done away” here in Mormon 8:26. For another case of variation between away and way in the history of the text, one that is more plausible, see under Helaman 7:15–16 for the expression “to give (a)way”.
Summary: Maintain in Mormon 8:26 the use of away in “miracles are done away”, the expected expression as well as the reading of the earliest textual sources.