Remove unused inet_* weak references

This change requires a Newlib from 2017-06-12 or later.

freebsd/lib/libc/inet/inet_addr.c

@@ -204,6 +204,7 @@ inet_aton(const char *cp, struct in_addr *addr) {
 	return (1);
 }
 
+#ifndef __rtems__
 /*
  * Weak aliases for applications that use certain private entry points,
  * and fail to include <arpa/inet.h>.
@@ -212,5 +213,6 @@ inet_aton(const char *cp, struct in_addr *addr) {
 __weak_reference(__inet_addr, inet_addr);
 #undef inet_aton
 __weak_reference(__inet_aton, inet_aton);
+#endif /* __rtems__ */
 
 /*! \file */