[asan] Enable halt_on_error tests on ARM targets

[ygribov]

Summary

This patch enables recent halt_on_error feature on ARM targets. We've tested it locally on Juno and it seems to work robustly (which is expected as the feature is rather primitive).

[rengolin]

Thanks Yuri! I'll run them here and will let you know ASAP.

[samsonov]

LGTM

[rengolin]

Both 39 and 42 VMA green, good to go, thanks!

test/asan/TestCases/Posix/halt_on_error-signals.c

 // Test interaction of Asan recovery mode with asynch signals.
 //
 // RUN: %clang_asan -fsanitize-recover=address -pthread %s -o %t
 //
 // RUN: rm -f %t.log
 // RUN: env ASAN_OPTIONS=halt_on_error=false %run %t 100 >%t.log 2>&1 || true
 // Collision will almost always get triggered but we still need to check the unlikely case:
 // RUN: FileCheck --check-prefix=CHECK-COLLISION %s < %t.log || FileCheck --check-prefix=CHECK-NO-COLLISION %s < %t.log
-//
-// REQUIRES: stable-runtime
 
 #define _SVID_SOURCE 1  // SA_NODEFER
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <pthread.h>
 #include <time.h>

test/asan/TestCases/Posix/halt_on_error-torture.cc

 // Stress test recovery mode with many threads.
 //
 // RUN: %clangxx_asan -fsanitize-recover=address -pthread %s -o %t
 //
 // RUN: env ASAN_OPTIONS=halt_on_error=false %run %t 1 10 >1.txt 2>&1
 // RUN: FileCheck %s < 1.txt
 // RUN: [ $(grep -c 'ERROR: AddressSanitizer: use-after-poison' 1.txt) -eq 10 ]
 // RUN: FileCheck --check-prefix=CHECK-NO-COLLISION %s < 1.txt
 //
 // Collisions are unlikely but still possible so we need the ||.
 // RUN: env ASAN_OPTIONS=halt_on_error=false %run %t 10 20 >10.txt 2>&1 || true
 // This one is racy although _very_ unlikely to fail:
 // RUN: FileCheck %s < 10.txt
 // RUN: FileCheck --check-prefix=CHECK-COLLISION %s < 1.txt || FileCheck --check-prefix=CHECK-NO-COLLISION %s < 1.txt
-//
-// REQUIRES: stable-runtime
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <pthread.h>
 #include <time.h>
 
 #include <sanitizer/asan_interface.h>