kmscube: Correct DEPENDS to avoid overwrite

As part of the below commit, DEPENDS gets overwrite which is wrong
Link: https://git.yoctoproject.org/poky/commit/?id=bd947d3343dcd96e79fc8157f32a2a087cd710a7



So correct the DEPENDS varibales

Signed-off-by: Ranjitsinh Rathod <ranjitsinh.rathod@kpit.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>