ARC: CONFIG_NODES_SHIFT fix default values

Seem like values assigned as absolute number and not and
shift value, i.e. should be 0 for one node (2^0) and 1 for
couple of nodes (2^1)
Signed-off-by: Noam Camus <noamca@mellanox.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/Kconfig

@@ -353,8 +353,8 @@ endchoice
 
 config NODES_SHIFT
 	int "Maximum NUMA Nodes (as a power of 2)"
-	default "1" if !DISCONTIGMEM
-	default "2" if DISCONTIGMEM
+	default "0" if !DISCONTIGMEM
+	default "1" if DISCONTIGMEM
 	depends on NEED_MULTIPLE_NODES
 	---help---
 	  Accessing memory beyond 1GB (with or w/o PAE) requires 2 memory