sparc: move CONFIG_{LEON, LEON2, LEON3} to Kconfig

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Daniel Hellstrom <daniel@gaisler.com>
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 24bdccb..56bdae6 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -4,17 +4,31 @@
 config SYS_ARCH
 	default "sparc"
 
+config LEON
+	bool
+
+config LEON2
+	bool
+	select LEON
+
+config LEON3
+	bool
+	select LEON
+
 choice
 	prompt "Board select"
 
 config TARGET_GRSIM_LEON2
 	bool "GRSIM simulating a LEON2 board"
+	select LEON2
 
 config TARGET_GR_CPCI_AX2000
 	bool "Gaisler GR-CPCI-AX2000 board"
+	select LEON3
 
 config TARGET_GR_EP2S60
 	bool "Gaisler Template design for Altera NIOS board with Stratix EP2S60"
+	select LEON3
 	help
 	  Gaisler Research AB's Template design (GPL Open Source SPARC/LEON3
 	  96MHz) for Altera NIOS Development board Stratix II edition,
@@ -22,9 +36,11 @@
 
 config TARGET_GR_XC3S_1500
 	bool "Gaisler GR-XC3S-1500 spartan board"
+	select LEON3
 
 config TARGET_GRSIM
 	bool "GRSIM simulating a LEON3 GR-XC3S-1500 board"
+	select LEON3
 
 endchoice