Add libqtappfw to DEPENDS for dashboard app for signal composer
event support, and to RDEPENDS as well as new runtime dependency
agl-service-signal-composer.
Bug-AGL: SPEC-3042
Change-Id: I955f821798d85fbb0f9265ee55b81ff0bd7db620 Signed-off-by: Scott Murray <scott.murray@konsulko.com>