This fixes the following failure when doing a clean build (in particular
no .ninja* lying around) of lib/libMLIRAMDGPUTransforms.a only:
```
In file included from mlir/lib/Dialect/AMDGPU/Transforms/OptimizeSharedMemory.cpp:21:
mlir/include/mlir/Dialect/Func/IR/FuncOps.h:29:10: fatal error: mlir/Dialect/Func/IR/FuncOps.h.inc: No such file or directory
```