tests: codegen-llvm: iter-repeat-n-trivial-drop: Allow non-zero lower bound to __rust_alloc size

LLVM emits a lower bound of 8 for the size parameter to __rust_alloc
when targeting x86_64-unknown-hermit. Since that is also completely
valid, relax the lower bound check.
diff --git a/tests/codegen-llvm/iter-repeat-n-trivial-drop.rs b/tests/codegen-llvm/iter-repeat-n-trivial-drop.rs
index a4e5c88..98e906d 100644
--- a/tests/codegen-llvm/iter-repeat-n-trivial-drop.rs
+++ b/tests/codegen-llvm/iter-repeat-n-trivial-drop.rs
@@ -47,7 +47,7 @@ pub fn iter_repeat_n_next(it: &mut std::iter::RepeatN<NotCopy>) -> Option<NotCop
 #[no_mangle]
 // CHECK-LABEL: @vec_extend_via_iter_repeat_n
 pub fn vec_extend_via_iter_repeat_n() -> Vec<u8> {
-    // CHECK: %[[ADDR:.+]] = tail call {{(noalias )?}}noundef dereferenceable_or_null(1234) ptr @{{.*}}__rust_alloc(i64 noundef {{(range\(i64 0, -9223372036854775808\) )?}}1234, i64 noundef {{(range\(i64 1, -9223372036854775807\) )?}}1)
+    // CHECK: %[[ADDR:.+]] = tail call {{(noalias )?}}noundef dereferenceable_or_null(1234) ptr @{{.*}}__rust_alloc(i64 noundef {{(range\(i64 [0-9]+, -9223372036854775808\) )?}}1234, i64 noundef {{(range\(i64 1, -9223372036854775807\) )?}}1)
     // CHECK: tail call void @llvm.memset.p0.i64(ptr noundef nonnull align 1 dereferenceable(1234) %[[ADDR]], i8 42, i64 1234,
 
     let n = 1234_usize;