[llvm] [AArch64] Fix extern_weak function calls on Windows (PR #219202)

[via llvm-commits]

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@@ -11,7 +11,7 @@ define void @func() nounwind {
 ; CHECK-NEXT:    ldr x8, [x8, :lo12:.refptr.weakfunc]
 ; CHECK-NEXT:    cbz x8, .LBB0_2
 ; CHECK-NEXT:  // %bb.1:
-; CHECK-NEXT:    blr x8
+; CHECK-NEXT:    bl weakfunc
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trcrsired wrote:

Manually added with isDSOLocal() check. Should be ok right?

https://github.com/llvm/llvm-project/pull/219202