weston: Do not override PACKAGECONFIG

PACKAGECONFIG should not be overridden. If not, it will become very
complex to enable other features defined in the main recipe.

This patch also removes the duplicate PACKAGECONFIG settings defined
in the bbappend after this change.

For sololite, remove egl from PACKAGECONFIG as egl is enabled by
default for DISTRO_FEATURES wayland.

Signed-off-by: Neena Busireddy <neena.busireddy@freescale.com>
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
u-boot-*: Add DESCRIPTION for u-boot providers

Add u-boot DESCRIPTION for those providers still using the default one.
This is needed in order to have a complete and readable list of u-boot providers
in FSL Community BSP Release Notes.

Signed-off-by: Daiane Angolini <daiane.angolini@freescale.com>
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>