Fix dependencies of code generated by llvm-tblgen

Let llvm-tblgen output .d files and use them instead of
hand-written dependencies. The hand-written dependencies
were incomplete. For example, nothing was regenerated by
modifying include/llvm/CodeGen/ValueTypes.td.

Bug: 27954979
Change-Id: I4c984be9593045bedd7f4feac995e15ed07623c4
5 files changed