[llvm] [AArch64] Always print the PRFM operation name (PR #182035)

[Kerry McLaughlin via llvm-commits]

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@@ -2226,11 +2226,11 @@ _func:
 // CHECK: ldr     x10, #-1048576          // encoding: [0x0a,0x00,0x80,0x58]
 
         prfm pldl1strm, nowhere
-        prfm #22, somewhere
+        prfm #25, somewhere
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kmclaughlin-arm wrote:

I wasn't entirely sure whether to change these or just update the check lines. But it seemed to me that there were two `prfm` instructions included in these tests, to check both an `Rt` value which does correlate to a `<prfop>` name and one that does not (and should be printed as an `#imm` value).
This is why I chose to update the value as well, so that we still have a test for each case.

https://github.com/llvm/llvm-project/pull/182035