[clang] [PowerPC][CLANG] DMF VSX Vector float GER 2x (rank-2 update) (PR #147383)

[Maryam Moghadas via cfe-commits]

================
@@ -1116,6 +1116,14 @@ UNALIASED_CUSTOM_MMA_BUILTIN(mma_xvbf16ger2, "vW512*VV",
                              "mma,paired-vector-memops")
----------------
maryammo wrote:

Missing a test for these builtins in `pc-dmf-future-builtin-err.c`  with `__attribute__((target("no-isa-future-instructions")))`.

https://github.com/llvm/llvm-project/pull/147383