trivial: fix typos/grammar errors in Kconfig texts

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/usb/serial/Kconfig

@@ -518,8 +518,8 @@ config USB_SERIAL_SIERRAWIRELESS
 	help
 	  Say M here if you want to use Sierra Wireless devices.
 
-	  Many deviecs have a feature known as TRU-Install, for those devices
-	  to work properly the USB Storage Sierra feature must be enabled.
+	  Many devices have a feature known as TRU-Install. For those devices
+	  to work properly, the USB Storage Sierra feature must be enabled.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called sierra.