Add missing va_end() to prevent stack corruptions

Added va_end() for copied variable arguments lists
in __vfprintf() and __find_arguments().
This is by C standard.
Important for systems which pass arguments in registers.

Change-Id: I7ac42beaa6645bfe856c18132253352dae29ea37

libc/stdio/vfprintf.c

@@ -827,6 +827,7 @@ error:
 		munmap(argtable, argtablesiz);
 		argtable = NULL;
 	}
+        va_end(orgap);
 	return (__sferror(fp) ? EOF : ret);
 	/* NOTREACHED */
 }