Sync with upstream OpenBSD: trivial stuff.

No active ingredient to any of these changes.

Bug: N/A
Test: builds
Change-Id: Ib1191a5c2826da024245d03dfc57557c8903a6cc
diff --git a/libc/upstream-openbsd/android/include/openbsd-compat.h b/libc/upstream-openbsd/android/include/openbsd-compat.h
index bec860b..9b16da7 100644
--- a/libc/upstream-openbsd/android/include/openbsd-compat.h
+++ b/libc/upstream-openbsd/android/include/openbsd-compat.h
@@ -22,6 +22,11 @@
 #include <sys/cdefs.h>
 #include <stddef.h> // For size_t.
 
+#define __BEGIN_HIDDEN_DECLS _Pragma("GCC visibility push(hidden)")
+#define __END_HIDDEN_DECLS _Pragma("GCC visibility pop")
+
+extern const char* __progname;
+
 /* Redirect internal C library calls to the public function. */
 #define _err err
 #define _errx errx