build/NetBSD: use kinfo_proc2; undef uint64_t (#8197)

closes #8196

For historical reasons, uint64_t and friends are defined both as 
typedefs and macros. Some platforms that do that define the macros as
identity (#define uint64_t uint64_t), others like NetBSD define to the
backing type (#define uint64_t __uint64_t). This is normally
transparent, except when multiple levels of macro expansions are used
inconsistently.

src/nvim/map.h

@@ -8,6 +8,11 @@
 #include "nvim/api/private/dispatch.h"
 #include "nvim/bufhl_defs.h"
 
+#if defined(__NetBSD__)
+# undef uint64_t
+# define uint64_t uint64_t
+#endif
+
 #define MAP_DECLS(T, U) \
   KHASH_DECLARE(T##_##U##_map, T, U) \
   \