diag: Edit event mask responses

This change rectifies incorrect handling of event mask requests.
PC tools send in requests like x60, x82 for diag events traffic.
x60 requires all event states to be toggled and x82 command
requires present status in its reponse.

Change-Id: I37aa51ef1e19f5a803c60e5a6f7b3b5c8776b3ff
Signed-off-by: Shalabh Jain <shalabhj@codeaurora.org>