test: Mark all rpass-valgrind as no-prefer-dynamic

This applies the same fix as added in 595d5b2 which is to just compile all
valgrind tests statically instead of dynamically. It looks like this is a
resurgence of either #30383 or #31328 in some weird fashion.

I'm not actually sure what's going on with the bots, and it's unclear whether
this is a valgrind bug or a libstd bug, but for now let's just get things
landing again.

Closes #30383

src/test/run-pass-valgrind/cast-enum-with-dtor.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// no-prefer-dynamic
+
 #![allow(dead_code)]
 #![feature(const_fn)]
 

src/test/run-pass-valgrind/cleanup-auto-borrow-obj.rs

@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// no-prefer-dynamic
 
 // This would previously leak the Box<Trait> because we wouldn't
 // schedule cleanups when auto borrowing trait objects.

src/test/run-pass-valgrind/cleanup-stdin.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// no-prefer-dynamic
+
 fn main() {
     let _ = std::io::stdin();
     let _ = std::io::stdout();

src/test/run-pass-valgrind/dst-dtor-1.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// no-prefer-dynamic
+
 static mut DROP_RAN: bool = false;
 
 struct Foo;

src/test/run-pass-valgrind/dst-dtor-2.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// no-prefer-dynamic
+
 static mut DROP_RAN: isize = 0;
 
 struct Foo;

src/test/run-pass-valgrind/exit-flushes.rs

@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// no-prefer-dynamic
 // ignore-macos this needs valgrind 3.11 or higher; see
 // https://github.com/rust-lang/rust/pull/30365#issuecomment-165763679
 

src/test/run-pass-valgrind/osx-frameworks.rs

@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// no-prefer-dynamic
 // pretty-expanded FIXME #23616
 
 #![feature(libc)]