entd: move opencryptoki initialization out of entd

Look for a file /home/chronos/.cryptohome-init-pkcs11 and expect cryptohome to initialize the PKCS#11 token, disabling that interface in newer extensions.

Change-Id: I363ec0ef093d58d793a3d75e22dee96b58bdacd3

R=rginda@chromium.org
BUG=chromium-os:12304
TEST=
old extension / new entd (w/ and w/o flag)
new extension / old entd:
new extension / new entd (w/ and w/o flag):

When flag is set with new entd, Initialize button disappears and we wait for cryptohomed to signal the TPM token is ready.

Review URL: http://codereview.chromium.org/6821025
7 files changed