[clang] [Driver] Add toolchain for X86_64 UEFI target (PR #76838)

[Fangrui Song via cfe-commits]

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@@ -22,6 +22,10 @@
 // RUN:     FileCheck --check-prefix=X86_64 %s
 // X86_64: target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
 
+// RUN: %clang_cc1 -triple x86_64-unknown-uefi -emit-llvm -o - %s | \
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MaskRay wrote:

With clang/test/CodeGen/X86/uefi-data-layout.c, this is unneeded

https://github.com/llvm/llvm-project/pull/76838