update David Miller's old email address

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

arch/mips/kernel/r4k_fpu.S

@@ -6,7 +6,7 @@
  * Copyright (C) 1996, 98, 99, 2000, 01 Ralf Baechle
  *
  * Multi-arch abstraction and asm macros for easier reading:
- * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
+ * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
  *
  * Carsten Langgaard, carstenl@mips.com
  * Copyright (C) 2000 MIPS Technologies, Inc.