Use libcxx's default rune table with the Musl C library.

Also, there are no exported character type tables from Musl so we have to
Fallback to the standard functions. This reduces the number of libcxx's
test-suite failures down to ~130 for MIPS. Most of the remaining failures
come from the atomics (due to the lack of 8-byte atomic-ops in MIPS32) and
thread tests.

Reviewers: mclow.lists, EricWF, dalias, jroelofs

Subscribers: tberghammer, danalbert, srhines, cfe-commits

Differential Revision:

git-svn-id: 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed