Add LinkAllPasses to clang

This patch ensures that no passes are deleted from clang, such that the loading
of plugins does not fail because of passes being unavailable.  This increases
the size of the clang binary from 43029853 to 43915291 bytes (around 2%).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143414 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed