Add run-pass-valgrind tests

Closes #16914
Move some tests to run-pass-valgrind
Make rpass-valgrind work with pretty
Remove support for .rc files from test.mk
Error if we should be able to Valgrind but can't
OS X 32 => BAD_VALGRIND
auto merge of #17868 : nick29581/rust/valgrind, r=alexcrichton

r? @alexcrichton