random: entropy tweaks are all the rage nowadays

use nonblocking for all.  Read this web page:
http://lwn.net/Articles/489734/

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>

Conflicts:

	drivers/char/random.c

Change-Id: Icceab0cbc0c71d05e1627663758382525bc998ca