Fix hangup in delImpl function

:Release Notes:
Remove hangup on del quiery

:Detailed Notes:
findImpl return objects with _del: true. Looks like
search query works not well and return deleted objects.
This is quick fix, that will ignore deleted objects.

:Testing Performed:
Compiled and tested localy.

:QA Notes:
luna-send -n 1 -a com.palm.configurator luna://com.palm.db/del '{"query":{"from":"com.webos.somekind:1","where":[{"prop":"key","op":"=", "val":"SomeValue"}] }}'

:Issues Addressed:
[GF-62692] db8 consumes 100% on testing

Open-webOS-DCO-1.0-Signed-off-by: Maksym Sditanov <maxim.sditanov@lge.com>

Change-Id: Ic75f27632e1f68aa39cf46b8f87afe89063bcac3
Reviewed-on: https://g2g.palm.com/5179
Reviewed-by: DCO Verification
Reviewed-by: Maksym Sditanov <maxim.sditanov@lge.com>
Tested-by: Maksym Sditanov <maxim.sditanov@lge.com>
Reviewed-by: Oleg Yablokov <oleg.yablokov@lge.com>
Reviewed-by: Andrii Motsok <andrii.motsok@lge.com>
Reviewed-by: Igor Kuksyuk <igor.kuksiuk@lge.com>