[SPARC]: introduce a SPARC Kconfig symbol

Introduce a Kconfig symbol SPARC that is defined on both the sparc and
sparc64 architectures.

This symbol makes some dependencies more readable.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc64/Kconfig b/arch/sparc64/Kconfig
index 3fded69..c4b7ad7 100644
--- a/arch/sparc64/Kconfig
+++ b/arch/sparc64/Kconfig
@@ -5,6 +5,10 @@
 
 mainmenu "Linux/UltraSPARC Kernel Configuration"
 
+config SPARC
+	bool
+	default y
+
 config SPARC64
 	bool
 	default y