swift234

In some cases, the same type error will result in different diagnostics being emitted between ARM and x86 targets.
Addressing rdar://problem/19434979 will allow us to swizzle expected errors based on build configuration options,
but until I can push that change we should generalize a few of the expected errors in the FixedPointDiagnostics test,
and re-enable the test on ARM.

Swift SVN r24910