[clang] [AArch64][SME2] Add PEXT, PSEL builtins for SME2 (PR #72827)

[Dinar Temirbulatov via cfe-commits]

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@@ -1859,19 +1859,28 @@ def SVBGRP   : SInst<"svbgrp[_{d}]",   "ddd", "UcUsUiUl", MergeNone, "aarch64_sv
 def SVBGRP_N : SInst<"svbgrp[_n_{d}]", "dda", "UcUsUiUl", MergeNone, "aarch64_sve_bgrp_x">;
 }
 
+let TargetGuard = "sve2p1|sme" in {
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dtemirbulatov wrote:

Accroding to https://developer.arm.com/documentation/ddi0602/2022-09/SVE-Instructions/PSEL--Predicate-select-between-predicate-register-or-all-false-?lang=en, it is "sve2p1" and "sme" both enabled, I think now it is `sve2p1,sme` should work.

https://github.com/llvm/llvm-project/pull/72827