After poky commit 4705dd264681d908f144dd4d9bf1f6175f68d8b9, soft dependencies
for complementary packages no longer get included by bitbake's internal package
managers. Make weston's dependency with wayland-protocols a hard one to include
wayland-protocols in our SDKs, which is how it used to be in older DEY
releases.
Signed-off-by: Gabriel Valcazar <gabriel.valcazar@digi.com>