[tsan] Fix freebsd build.

[yabinc]

Summary

Freebsd doesn't have <sys/personality.h>, so call personality() only in
SANITIZER_LINUX.

[beanz]

LGTM

lib/tsan/rtl/tsan_platform_linux.cc

 #include <fcntl.h>
 #include <pthread.h>
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdarg.h>
 #include <sys/mman.h>
+#if SANITIZER_LINUX
 #include <sys/personality.h>
+#endif
 #include <sys/syscall.h>
 #include <sys/socket.h>
 #include <sys/time.h>
 #include <sys/types.h>
 #include <sys/resource.h>
 #include <sys/stat.h>
 #include <unistd.h>
 #include <errno.h>
if (kCppMode) {
 
     if (!AddressSpaceIsUnlimited()) {
       Report("WARNING: Program is run with limited virtual address space,"
              " which wouldn't work with ThreadSanitizer.\n");
       Report("Re-execing with unlimited virtual address space.\n");
       SetAddressSpaceUnlimited();
       reexec = true;
     }
-#if defined(__aarch64__)
+#if SANITIZER_LINUX && defined(__aarch64__)
     // After patch "arm64: mm: support ARCH_MMAP_RND_BITS." is introduced in
     // linux kernel, the random gap between stack and mapped area is increased
     // from 128M to 36G on 39-bit aarch64. As it is almost impossible to cover
     // this big range, we should disable randomized virtual space on aarch64.
     int old_personality = personality(0xffffffff);
     if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) {
       VReport(1, "WARNING: Program is run with randomized virtual address "
               "space, which wouldn't work with ThreadSanitizer.\n"