[llvm] [GlobalISel] Don't permit G_*MIN/G_*MAX of pointer vectors (PR #168872)

[Matt Arsenault via llvm-commits]

================
@@ -0,0 +1,35 @@
+#RUN: not --crash llc -o - -mtriple=arm64 -global-isel -run-pass=none -verify-machineinstrs %s 2>&1 | FileCheck %s
+# REQUIRES: aarch64-registered-target
+
+---
+name:            test_minmax
+legalized:       true
+regBankSelected: false
+selected:        false
+tracksRegLiveness: true
+liveins:
----------------
arsenm wrote:

```suggestion
```

https://github.com/llvm/llvm-project/pull/168872