[llvm] [Mips] Fix clang crashes when assembling invalid MIPS beql instructions with --arch=mips (PR #156413)

[Matt Arsenault via llvm-commits]

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@@ -1,5 +1,9 @@
 # RUN: not llvm-mc %s -triple=mips -mcpu=mips32 2>&1 | FileCheck %s
 
+# CHECK: error: invalid operand for instruction
+  beql $t0, ($t0), 1
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arsenm wrote:

This changed at least 2 opcodes, right? Should test all of them (missing bne?)

https://github.com/llvm/llvm-project/pull/156413