Don't declare target initialization functions ourself, let
llvm-c/Target.h do it for us.  In fact this header was being dragged in already,
and causing clang to error out when compiling this file due to the duplicate
declarations.  Fixes PR15903.


git-svn-id: https://llvm.org/svn/llvm-project/dragonegg/trunk@181030 91177308-0d34-0410-b5e6-96231b3b80d8