[X86][AMX] Replace PXOR instruction with SET0 in AMX pre config.
To generate zero value, the PXOR instruction need 3 operands that is tied to the same vreg. If is not good in SSA form and with undef value two address instruction pass may convert `%0:vr128 = PXORrr undef %0, undef %0` to `%1:vr128 = PXORrr undef %1:vr128(tied-def 0), undef %0:vr128`. It is not expected. It can be simplified to SET0 instruction which only take 1 destination operand. It should be more friendly to two address instruction pass and register allocation pass. `%0:vr128 = V_SET0` Also add AVX1 code path so that it is consistant to other code. Differential Revision: https://reviews.llvm.org/D124903
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