wpa_supplicant: Permit the at_console user access to the

wpa_supplicant: Permit the at_console user access to the
root properties of wpa_supplicant, so that they can set the debug
variables. The properties at this node are three debug variables
(writable) and lists of interfaces and EAP methods (read-only).

BUG=8984
TEST=Remove sudo from wpa_debug (separate CL) and run as chronos
user. Check for error, as opposed to a valid response.

Change-Id: I46479510b2b32be7eaa98ae860bdd8c4f91521e5

Committed: http://chrome-svn/viewvc/chromeos?view=rev&revision=46eb824

[Nathan Williams, 2010-11-10 21:59:25]

I believe this is the minimal amount we can expose to the user, since the choice
of variable is a string parameter to the Get or Set method. Provided we don't
add any sensitive properties here, this should be fine.

[Sam Leffler, 2010-11-10 22:05:41]

LGTM