tests: adapt array-cmp for llvm/llvm-project@f7b65011de51

The referenced commit adds a new llvm.loop.estimated_trip_count metadata
entry, which shows up in this test. It was being erroneously captured by
a too-broad regular expression, which this fixes such that the test
passes both before and after the upstream change.

@rustbot label llvm-main

Author: durin42

tests/codegen-llvm/array-cmp.rs

@@ -46,7 +46,7 @@ pub fn array_of_tuple_le(a: &[(i16, u16); 2], b: &[(i16, u16); 2]) -> bool {
     // CHECK: %[[B01:.+]] = load i16, ptr %[[PB01]]
     // CHECK-NOT: cmp
     // CHECK: %[[EQ01:.+]] = icmp eq i16 %[[A01]], %[[B01]]
-    // CHECK-NEXT: br i1 %[[EQ01]], label %[[L10:.+]], label %[[EXIT_U:.+]]
+    // CHECK-NEXT: br i1 %[[EQ01]], label %[[L10:.+]], label %[[EXIT_U:.+]]{{(, !llvm.loop ![0-9+])?}}
 
     // CHECK: [[L10]]:
     // CHECK: %[[PA10:.+]] = getelementptr{{.+}}i8, ptr %a, {{i32|i64}} 4