Edje entry: Use markup text for password in preedit mode

Edje entry: Use markup text for password in preedit mode

Summary:
Use markup text for password in preedit mode

Problem is that when text comes in preedit mode
it is always markup text and when it is committed
to entry it got committed with markup tags along with
the original string, so for preedit mode password
should be filtered all markup to set the proper text.

@fix

Test Plan:
In preedit mode, enter any character say 'A'
preedit markup like <preedit>A</preedit>
will come in preedit changed callback

Result: Text is set as plain text like below
&lt;preedit&gt;A&lt;/preedit&gt;

Reviewers: thiepha, jihoon, herdsman, shilpasingh, tasn

Reviewed By: shilpasingh, tasn

Subscribers: cedric

Differential Revision: https://phab.enlightenment.org/D2929

Change-Id: Ib53e9cc414ab2e84bba27adfd6676c5d32d150ac