MAINTAINERS: Change list for ioc_serial to linux-serial.

IOC3 is also being used on SGI MIPS systems but this particular driver is
only being used on IA64 systems so linux-mips made no sense as a list.  Pat
also thinks linux-serial@vger.kernel.org is the better list.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index f46d8e6..1117403 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3140,7 +3140,7 @@
 
 IOC3 SERIAL DRIVER
 M:	Pat Gefre <pfg@sgi.com>
-L:	linux-mips@linux-mips.org
+L:	linux-serial@vger.kernel.org
 S:	Maintained
 F:	drivers/serial/ioc3_serial.c