Disable close_range test for musl

Musl doesn't have close_range, skip the test.

Bug: 190084016
Test: m USE_HOST_MUSL=true host-native
Change-Id: I7ed485f2d0ec08358c856430b7c4c45fbe45a39f
diff --git a/tests/unistd_test.cpp b/tests/unistd_test.cpp
index 49fec12..02da585 100644
--- a/tests/unistd_test.cpp
+++ b/tests/unistd_test.cpp
@@ -1652,6 +1652,8 @@
 TEST(UNISTD_TEST, close_range) {
 #if defined(__GLIBC__)
   GTEST_SKIP() << "glibc too old";
+#elif defined(ANDROID_HOST_MUSL)
+  GTEST_SKIP() << "musl does not have close_range";
 #else   // __GLIBC__
   int fd = open("/proc/version", O_RDONLY);
   ASSERT_GE(fd, 0);
@@ -1683,4 +1685,4 @@
   ASSERT_TRUE(android::base::ReadFdToString(tf2.fd, &content));
   ASSERT_EQ("hello world", content);
 #endif  // __GLIBC__
-}
\ No newline at end of file
+}