Clean up initialization of empfile[]

Split ef_init() into two functions: empfile_init() for initialization,
and empfile_fixup() to fix it up for configuration.  Put them next to
empfile[].  Move the call to empfile_init() from behind emp_config()
to before it.

src/server/main.c

@@ -211,9 +211,10 @@ main(int argc, char **argv)
     }
 #endif	/* _WIN32 */
 
+    empfile_init();
     if (emp_config(config_file) < 0)
 	exit(EXIT_FAILURE);
-    ef_init();
+    empfile_fixup();
     if (read_builtin_tables() < 0)
 	exit(EXIT_FAILURE);
     if (read_custom_tables() < 0)