Add NetBSD support in sanitizer_procmaps.h

[krytarowski]

Summary

Reuse Linux and FreeBSD - no NetBSD specific changes.

Part of the code inspired by the original work on libsanitizer in GCC 5.4 by Christos Zoulas.

Sponsored by <The NetBSD Foundation>

[filcab]

LGTM

lib/sanitizer_common/sanitizer_procmaps.h

 #define SANITIZER_PROCMAPS_H
 
 #include "sanitizer_common.h"
 #include "sanitizer_internal_defs.h"
 #include "sanitizer_mutex.h"
 
 namespace __sanitizer {
 
-#if SANITIZER_FREEBSD || SANITIZER_LINUX
+#if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD
 struct ProcSelfMapsBuff {
   char *data;
   uptr mmaped_size;
   uptr len;
 };
 
 // Reads process memory map in an OS-specific way.
 void ReadProcMaps(ProcSelfMapsBuff *proc_maps);
-#endif  // SANITIZER_FREEBSD || SANITIZER_LINUX
+#endif  // SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD
 
 // Memory protection masks.
 static const uptr kProtectionRead = 1;
 static const uptr kProtectionWrite = 2;
 static const uptr kProtectionExecute = 4;
 static const uptr kProtectionShared = 8;
 
 struct MemoryMappedSegment {
public:
   // Adds all mapped objects into a vector.
   void DumpListOfModules(InternalMmapVector<LoadedModule> *modules);
 
  private:
   void LoadFromCache();
 
   // FIXME: Hide implementation details for different platforms in
   // platform-specific files.
-# if SANITIZER_FREEBSD || SANITIZER_LINUX
+# if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD
   ProcSelfMapsBuff proc_self_maps_;
   const char *current_;
 
   // Static mappings cache.
   static ProcSelfMapsBuff cached_proc_self_maps_;
   static StaticSpinMutex cache_lock_;  // protects cached_proc_self_maps_.
 # elif SANITIZER_MAC
   template <u32 kLCSegment, typename SegmentCommand>