Move CONFIG_DEVKMEM default to n

Kconfig comment suggests setting it as "n" if in doubt thus move the
default value to 'n'.
Signed-off-by: Dave Young <dyoung@redhat.com>
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/char/Kconfig

@@ -17,7 +17,6 @@ config DEVMEM
 
 config DEVKMEM
 	bool "/dev/kmem virtual device support"
-	default y
 	help
 	  Say Y here if you want to support the /dev/kmem device. The
 	  /dev/kmem device is rarely used, but can be used for certain