[llvm] Fix mechanism propagating mangled names for TLI function mappings (PR #66656)

[Paul Walker via llvm-commits]

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@@ -14,7 +14,7 @@
 
 #if defined(TLI_DEFINE_MASSV_VECFUNCS_NAMES)
 #define TLI_DEFINE_MASSV_VECFUNCS
-#define TLI_DEFINE_VECFUNC(SCAL, VEC, VF) VEC,
+#define TLI_DEFINE_VECFUNC(SCAL, VEC, VF, MANGLN) VEC,
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paulwalker-arm wrote:

Now that we've settled on just storing the prefix I suggest `VABI_PREFIX` as a more accurate name.

https://github.com/llvm/llvm-project/pull/66656