Fix Trac #8754 in a round-about way.
For some reason on OS X, it seems like -Bsymbolic (which we use for
hooks into the RTS) isn't working, which results in Trac #8754, where stats
don't work because defaultHooks doesn't initialize the stats flag. This
seems to work on Linux static/dynamically, but only on OS X statically.
After talking with Simon, really, the entire hooks thing is a bit
fragile. For now, we just work around it (since GHCi is dynamically
linked) by calling into the defaultHooks ourselves when GHC starts.
Signed-off-by: Austin Seipp <email@example.com>