59e6658381
We fixed a race condition in #51505 and #51107. This required running
autoreconfHook to pick up the `coregrind-makefile-race.patch` patch.
Unfortunately this broke darwin's postPatch fixes as autoreconfHook would run
afterwards regenerating the fixed makefiles.
Moving the postPatch fixes to preConfigure should resolve the issue.
I left `postPatch = ""` in to avoid a rebuild on linux.
(cherry picked from commit a6d4a0c53c)