Remove GENERIC_HARDIRQ config option

After the last architecture switched to generic hard irqs the config
options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code
for !CONFIG_GENERIC_HARDIRQS can be removed.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/net/Kconfig b/net/Kconfig
index ee02136..b50dacc 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -228,7 +228,7 @@
 
 config RFS_ACCEL
 	boolean
-	depends on RPS && GENERIC_HARDIRQS
+	depends on RPS
 	select CPU_RMAP
 	default y