typo fixes

Most of these fixes were already submitted for old kernel versions, and were
approved, but for some reason they never made it into the releases.

Because this is a consolidation of a couple old missed patches, it touches both
Kconfigs and documentation texts.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
diff --git a/net/9p/Kconfig b/net/9p/Kconfig
index eecbf12..71bc110 100644
--- a/net/9p/Kconfig
+++ b/net/9p/Kconfig
@@ -27,5 +27,5 @@
 	bool "Debug information"
 	depends on NET_9P
 	help
-	  Say Y if you want the 9P subsistem to log debug information.
+	  Say Y if you want the 9P subsystem to log debug information.