nios2: move generic config to boards.cfg

I can't build test this, but just looking at the config files written
and it seems OK ...

Tested-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
diff --git a/MAKEALL b/MAKEALL
index 51db13e..e37000f 100755
--- a/MAKEALL
+++ b/MAKEALL
@@ -553,9 +553,7 @@
 ## Nios-II Systems
 #########################################################################
 
-LIST_nios2="$(boards_by_arch nios2)
-	nios2-generic	\
-"
+LIST_nios2="$(boards_by_arch nios2)"
 
 #########################################################################
 ## MicroBlaze Systems