MAINTAINERS: Update BCM63XX entry

There are more files being supported by the BCM63XX than simply
"arch/arm/mach-bcm/bcm63xx.c" and "arch/arm/include/debug/bcm63xx.S".
Add a regex of "bcm63xx" to catch all the other files that are out
there.

Signed-off-by: Jon Mason <jon.mason@broadcom.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

MAINTAINERS

@@ -2525,8 +2525,7 @@ M:	bcm-kernel-feedback-list@broadcom.com
 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 T:	git git://github.com/broadcom/stblinux.git
 S:	Maintained
-F:	arch/arm/mach-bcm/bcm63xx.c
-F:	arch/arm/include/debug/bcm63xx.S
+N:	bcm63xx
 
 BROADCOM BCM63XX/BCM33XX UDC DRIVER
 M:	Kevin Cernekee <cernekee@gmail.com>