DELIA-58564: Channel Flip +/- Buttons Mapped Incorrectly

Reason for change: Youtube TV requires ch+ and Ch- keys mapped correctly.
Test Procedure: refer ticket.
Risks: None
Priority: P1
Signed-off-by: sramul630 <sunil_ramulu@comcast.com>

Change-Id: I45c5eed8e1f97bc1761ab1cc116e01d3bd722302