swift234

[driver] Added support for differentiating SIL emitted by -emit-sil and -emit-silgen.

SIL emitted by -emit-silgen is treated internally as “raw-sil”, while SIL emitted by -emit-silgen is treated internally as “sil".
Externally, there are no changes; both kinds of SIL still have a “.sil” file extension.
Updated test/Driver/Actions.swift to account for the change in behavior with -emit-silgen.

Swift SVN r10947