[llvm] Allow MAY(R)? to accept the high components of register pairs (PR #98606)

[Ulrich Weigand via llvm-commits]

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@@ -4176,12 +4176,9 @@
 #CHECK: may	%f0, %f0, -1
 #CHECK: error: invalid operand
 #CHECK: may	%f0, %f0, 4096
-#CHECK: error: invalid register pair
-#CHECK: may	%f2, %f0, 0
 
 	may	%f0, %f0, -1
 	may	%f0, %f0, 4096
-	may	%f2, %f0, 0
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uweigand wrote:

Oh, one more thing:  in addition to removing the `insn-bad` error check, can you please add a _positive_ test to `insn-good` that this is actually accepted?  This is quite unusual, and it would be good to have a test that catches any accidental regression here.

https://github.com/llvm/llvm-project/pull/98606