aries | p1: drivers: char: entropy tweaks are all the rage nowadays

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

Change-Id: I79ade1326d0f5a5cb0f76126cb1e8a56375fa040
Merge "aries | p1: drivers: char: entropy tweaks are all the rage nowadays" into android-4.4