MAINTAINERS: add raspberrypi to BCM2835 architecture

Recent changes to the firmware clock driver have not be send
to the architecture maintainers. So fix this by adding the
matching pattern.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

MAINTAINERS

@@ -3752,6 +3752,7 @@ F:	drivers/pci/controller/pcie-brcmstb.c
 F:	drivers/staging/vc04_services
 N:	bcm2711
 N:	bcm283*
+N:	raspberrypi
 BROADCOM BCM281XX/BCM11XXX/BCM216XX ARM ARCHITECTURE
 M:	Florian Fainelli <f.fainelli@gmail.com>