Fix tsan/asan/hwasan/etc failures on Android (#2229)

Some people run their benchmarks with sanitizers, and they should not spuriously fail. Asan and other sanitizer allocators return 0 for all mallopt calls, so the previous code was causing teh BM_CHECK to trigger.

src/benchmark.cc

diff --git a/src/benchmark.cc b/src/benchmark.cc
index c7baa10..22a395d 100644
--- a/src/benchmark.cc
+++ b/src/benchmark.cc
@@ -996,7 +996,9 @@
   // Android 12 (API level 31) introduced zeroing of allocated memory in bionic
   // as a hardening feature; however, this is not enabled for apps.
   if (__builtin_available(android 31, *)) {
-    BM_CHECK_EQ(mallopt(M_BIONIC_ZERO_INIT, 0), 1);
+    // Not asserting on the return value, as sanitizers interpose the allocator
+    // and always return 0
+    (void)mallopt(M_BIONIC_ZERO_INIT, 0);
   }
 
   // The default configuration of bionic is to return pages to the OS as soon
@@ -1004,7 +1006,7 @@
   // delay before returning memory to avoid excessive faulting on repeated
   // allocation and deallocation, which is common in repeated benchmark runs.
   if (__builtin_available(android 27, *)) {
-    BM_CHECK_EQ(mallopt(M_DECAY_TIME, 1), 1);
+    (void)mallopt(M_DECAY_TIME, 1);
   }
 #endif
   internal::HelperPrintf = HelperPrintf;