SH: add proper prompt to SH_MAGIC_PANEL_R2_VERSION

---
Tested with make ARCH=sh menuconfig

The new prompt isn't very informative. But at least it's better than the current, well, self referential prompt. SuperH is orphaned, so chances are we'll never see anything better.

By the way: why do the kconfig tools allow unquoted prompts?

 arch/sh/boards/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index e331e5373b8e..89963d13f930 100644
@@ -371,7 +371,7 @@ if SH_MAGIC_PANEL_R2
 menu "Magic Panel R2 options"
 
 config SH_MAGIC_PANEL_R2_VERSION
-	int SH_MAGIC_PANEL_R2_VERSION
+	int "Magic Panel R2 Version"
 	default "3"
 	help
 	  Set the version of the Magic Panel R2

1.9.3