[llvm] [AMDGPU][MC] Add dpp for V_PK_FMAC_F16 for GFX10 (PR #79598)

[Matt Arsenault via llvm-commits]

arsenm wrote:

> > It's there, but not spelled out (it says "V_PK_*")
> 
> The "V_PK_*" is in the VOP3P section of the table and `v_pk_fmac_f16` is a VOP2 opcode. The VOP2 section only has exceptions for `FMAMK/AD_F32/16` and 64bit opcodes. So according to the table, `v_pk_fmac_f16` should support DPP.

In the internal doc I see a nodpp flag on it still 

https://github.com/llvm/llvm-project/pull/79598