[e-mod-tizen-screen-reader] Emit hover events of ONGOING state in interval of 200ms

[e-mod-tizen-screen-reader] Emit hover events of ONGOING state in interval of 200ms

On hover, gesture update is sent continously which degrades
performance. Screen Reader is bombarded with continous unneccesary
updates about hover which causes performance issues for feature like
scroll audio feedback. Limiting hover events to 200ms intervals helps
to fix this.

Change-Id: I0f9e546d099b0eca8e3dfef033f8fbfadc4c3376
Signed-off-by: Prasoon Singh <prasoon.16@samsung.com>
(cherry picked from commit 25e6aa0df955a290b10363257bed3379ecfbd763)