Add some help texts to recently-introduced kconfig items

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (edited MACINTOSH_DRIVERS per Geert Uytterhoeven's remark)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/atm/Kconfig b/drivers/atm/Kconfig
index bed9f58..b554eda 100644
--- a/drivers/atm/Kconfig
+++ b/drivers/atm/Kconfig
@@ -6,6 +6,11 @@
 	bool "ATM drivers"
 	depends on NETDEVICES && ATM
 	default y
+	---help---
+	  Say Y here to get to see options for Asynchronous Transfer Mode
+	  device drivers. This option alone does not add any kernel code.
+
+	  If you say N, all options in this submenu will be skipped and disabled.
 
 if ATM_DRIVERS && NETDEVICES && ATM