This fixes the following failure when doing a clean build (in particular no .ninja* lying around) of lib/libMLIRNVVMToLLVM.a only: ``` In file included from mlir/lib/Conversion/NVVMToLLVM/NVVMToLLVM.cpp:18: mlir/include/mlir/Dialect/Func/IR/FuncOps.h:29:10: fatal error: mlir/Dialect/Func/IR/FuncOps.h.inc: No such file or directory ```