Fix several typos in drivers/

Signed-off-by: Adrian Bunk <bunk@stusta.de>
diff --git a/drivers/rapidio/Kconfig b/drivers/rapidio/Kconfig
index 0b2d2c3..4142115 100644
--- a/drivers/rapidio/Kconfig
+++ b/drivers/rapidio/Kconfig
@@ -15,4 +15,4 @@
 	default "30"
 	---help---
 	  Amount of time a discovery node waits for a host to complete
-	  enumeration beforing giving up.
+	  enumeration before giving up.