[llvm] [LoongArch] Use fallback path when relocation `SymA == nullptr` (PR #196940)

[Lu Weining via llvm-commits]

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@@ -69,6 +71,10 @@ la.pcrel $a0, z
 .4byte y-x
 .8byte .-x
 .4byte .-y
+1:
+.4byte 0xbeef-1b
+1:
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SixWeining wrote:

My bad. Thanks.

https://github.com/llvm/llvm-project/pull/196940