Remove unnecessary 'extern's.

Change-Id: Iba2b3fb6ff88e504f1657b915120ae43d58a1e03
diff --git a/libc/include/sys/fsuid.h b/libc/include/sys/fsuid.h
index 223db90..e4d9ebc 100644
--- a/libc/include/sys/fsuid.h
+++ b/libc/include/sys/fsuid.h
@@ -34,8 +34,8 @@
 
 __BEGIN_DECLS
 
-extern int setfsuid(uid_t) __INTRODUCED_IN(21);
-extern int setfsgid(gid_t) __INTRODUCED_IN(21);
+int setfsuid(uid_t) __INTRODUCED_IN(21);
+int setfsgid(gid_t) __INTRODUCED_IN(21);
 
 __END_DECLS