samples: drivers: kscan: enable logging, and add RK055HDMIPI4M shield

Enable logging by default in kscan sample, so that user will see output
even if they do not have a keyboard connected that follows the keymap.
Add a specific testcase for boards that support the RK055HDMIPI4M
display.

Signed-off-by: Daniel DeGrasse <daniel.degrasse@nxp.com>