[lsan][test] Enable many_tls_keys_pthread.cpp and disable swapcontext.cpp/fork_and_leak.cpp

With D98926, many_tls_keys_pthread.cpp appears to be working.

On glibc 2.30-0ubuntu2, swapcontext.cpp and Linux/fork_and_leak.cpp work fine
but they strangely fail on clang-cmake-aarch64-full
(https://lab.llvm.org/buildbot/#/builders/7/builds/2240).
Disable them for now.

Note: check-lsan was recently enabled on AArch64 in D98985. A test takes
10+ seconds. We should figure out the bottleneck.

Author: MaskRay

compiler-rt/test/lsan/TestCases/Linux/fork_and_leak.cpp

@@ -1,6 +1,9 @@
 // Test that leaks detected after forking without exec().
 // RUN: %clangxx_lsan %s -o %t && not %run %t 2>&1 | FileCheck %s
 
+/// Fails on clang-cmake-aarch64-full (glibc 2.27-3ubuntu1.4).
+// UNSUPPORTED: aarch64
+
 #include <assert.h>
 #include <stdlib.h>
 #include <sys/wait.h>

compiler-rt/test/lsan/TestCases/many_tls_keys_pthread.cpp

@@ -7,7 +7,7 @@
 
 // On glibc, this requires the range returned by GetTLS to include
 // specific_1stblock and specific in `struct pthread`.
-// UNSUPPORTED: arm-linux, armhf-linux, aarch64
+// UNSUPPORTED: arm-linux, armhf-linux
 
 // TSD on NetBSD does not use TLS
 // UNSUPPORTED: netbsd

compiler-rt/test/lsan/TestCases/swapcontext.cpp

@@ -5,7 +5,7 @@
 // RUN: %env_lsan_opts= %run %t 2>&1
 // RUN: %env_lsan_opts= not %run %t foo 2>&1 | FileCheck %s
 // Missing 'getcontext' and 'makecontext' on Android.
-// UNSUPPORTED: arm,powerpc64,android
+// UNSUPPORTED: arm,aarch64,powerpc64,android
 
 #include "sanitizer_common/sanitizer_ucontext.h"
 #include <stdio.h>