Problem in AMDGPU TableGen files

[Paul_C_Anagnostopoul]

A similar problem occurs in ARMInstrNEON.td, starting with:

  defm VADDLu : N3VLExt_QHS<1,1,0b0000,0, IIC_VSHLiD, IIC_VSHLiD,
                              "vaddl", "u", add, zanyext, 1>;

zanyext is of the wrong class.