Support for Artila M-501 starter kit

Kimmo Leppala / Sysart and
Timo Tuunainen / Sysart
diff --git a/Makefile b/Makefile
index 3b339ad..1effd6e 100644
--- a/Makefile
+++ b/Makefile
@@ -2308,6 +2308,8 @@
 mp2usb_config	:	unconfig
 	@$(MKCONFIG) $(@:_config=) arm arm920t mp2usb NULL at91rm9200
 
+m501sk_config	:	unconfig
+	@$(MKCONFIG) $(@:_config=) arm arm920t m501sk NULL at91rm9200
 
 ########################################################################
 ## ARM Integrator boards - see doc/README-integrator for more info.