android: binder: deal with contexts in debugfs.

Properly print the context in debugfs entries.

Change-Id: If10c2129536d9f39bae542afd7318ca79af60e3a
Signed-off-by: Martijn Coenen <maco@google.com>
Git-commit: db7c98ee
Git-repo: https://android.googlesource.com/kernel/common


Signed-off-by: Swetha Chikkaboraiah <schikk@codeaurora.org>