Make "disable memory mitigations" and "set heap tagging level" more available.

These were only available internally via android_mallopt(), but they're
likely to be needed by more code in future, so move them into mallopt().

This change leaves the android_mallopt() options for now, but I plan on
coming back to remove them after I've switched the handful of callers
over to mallopt() instead.

Bug: http://b/135772972
Test: treehugger
Change-Id: Ia154614069a7623c6aca85975a91e6a156f04759
diff --git a/tests/malloc_test.cpp b/tests/malloc_test.cpp
index bddd9ab..b35bba9 100644
--- a/tests/malloc_test.cpp
+++ b/tests/malloc_test.cpp
@@ -1256,7 +1256,7 @@
 #endif
 }
 
-TEST(android_mallopt, disable_memory_mitigations) {
+TEST(malloc, disable_memory_mitigations) {
 #if defined(__BIONIC__)
   if (!mte_supported()) {
     GTEST_SKIP() << "This function can only be tested with MTE";
@@ -1275,7 +1275,7 @@
                    },
                    &sem));
 
-  ASSERT_TRUE(android_mallopt(M_DISABLE_MEMORY_MITIGATIONS, nullptr, 0));
+  ASSERT_EQ(1, mallopt(M_BIONIC_DISABLE_MEMORY_MITIGATIONS, 0));
   ASSERT_EQ(0, sem_post(&sem));
 
   int my_tagged_addr_ctrl = prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0);