Fixes ENYO-556

## Issue
Regression from BHV-4645 - By moving the onSpotlightSelect dispatch to the key up handler, the key down handler handles the Enter key by dropping out of pointer mode and spotting the nearest control and the key up handler then selects the active control causing the popup to render.

## Fix
Remember that a control was spotted as a result of a key down event and, if so, kick out of spotlight's key up handler to avoid taking a second Spotlight action on the same key press.

Enyo-DCO-1.1-Signed-off-by: Ryan Duffy (ryan.duffy@lge.com)
@ryanjduffy, I am probably being nitpicky on this one, but I think I'd rather see this variable called something more like `_bFocusedOnKeyDown`, or maybe `_bSuppressSelectOnNextKeyUp`. I think the current name makes it sound like a configuration option rather than a state variable.