Build bionic unit tests for musl

Modify bionic unit tests that are built for glibc so that they also
build against musl.  They don't all pass though:

With glibc:
 2 SLOW TESTS
 4 TIMEOUT TESTS
313 FAILED TESTS
  YOU HAVE 2 DISABLED TESTS

With musl:
11 SLOW TESTS
11 TIMEOUT TESTS
363 FAILED TESTS
  YOU HAVE 2 DISABLED TESTS

Bug: 190084016
Test: m bionic-unit-tests-glibc with musl
Test: atest bionic-unit-tests-static
Test: atest --host bionic-unit-tests-glibc with glibc
Change-Id: I79b6eab04fed3cc4392450df5eef2579412edfe1
diff --git a/tests/sys_vfs_test.cpp b/tests/sys_vfs_test.cpp
index f82f505..242f8d4 100644
--- a/tests/sys_vfs_test.cpp
+++ b/tests/sys_vfs_test.cpp
@@ -51,7 +51,7 @@
   ASSERT_EQ(ENOENT, errno);
 }
 
-TEST(sys_vfs, statfs64) {
+TEST(sys_vfs, statfs64_smoke) {
   struct statfs64 sb;
   ASSERT_EQ(0, statfs64("/proc", &sb));
   Check(sb);
@@ -79,7 +79,7 @@
   ASSERT_EQ(EBADF, errno);
 }
 
-TEST(sys_vfs, fstatfs64) {
+TEST(sys_vfs, fstatfs64_smoke) {
   struct statfs64 sb;
   int fd = open("/proc", O_RDONLY);
   ASSERT_EQ(0, fstatfs64(fd, &sb));