[scudo] Do not include sanitizer_posix.h if not on a Posix platform
Summary:
Move the `sanitizer_posix.h` include within the `SANITIZER_ANDROID` `#if`,
otherwise this errors when built on non-Posix platforms (eg: Fuchsia).
Reviewers: alekseyshl
Subscribers: llvm-commits
#include "scudo_utils.h"
-#include "sanitizer_common/sanitizer_posix.h"
-
#include <stdarg.h>
#if defined(__x86_64__) || defined(__i386__)
# include <cpuid.h>
# if SANITIZER_ANDROID && __ANDROID_API__ < 18
// getauxval() was introduced with API level 18 on Android. Emulate it using
// /proc/self/auxv for lower API levels.
+# include "sanitizer_common/sanitizer_posix.h"
+
# include <fcntl.h>
# define AT_HWCAP 16
