Add ATSTK100[234] to MAINTAINERS

Add all the ATSTK1000 daughterboards to MAINTAINERS along with their
"mother". Also update the entry for ATSTK1000 to be not only about the
AP7000 CPU; it's intended to handle all CPUs in the AT32AP family.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

MAINTAINERS

@@ -630,7 +630,10 @@ Hayden Fraser <Hayden.Fraser@freescale.com>
 
 Haavard Skinnemoen <hskinnemoen@atmel.com>
 
-	ATSTK1000		AT32AP7000
+	ATSTK1000		AT32AP7xxx
+	ATSTK1002		AT32AP7000
+	ATSTK1003		AT32AP7001
+	ATSTK1004		AT32AP7002
 
 #########################################################################
 # End of MAINTAINERS list						#