PASTA LLVM patches should be a feature #961
Description
#959 added a patch that introduced a new feature in LLVM.
Upstream vcpkg does not allow patches that add new features, but since this is a repo dedicated to supporting the Lifting Bits organization tools, I allowed it.
However, there is valid concern that this patch could introduce bugs.
The proposed solution is to gate the patch behind a feature flag pasta and only include the patch if that feature is selected. Furthermore, the list of downloads for pre-built cxx-common will now have both the vanilla LLVM and patched LLVM per machine configuration.