packagegroup: rename to packagegroups

For consistency with other layers, like poky and meta-openembedded,
it's better to have packagegroup(s) directory in the plural version.

This patch prepares the source tree to have the single packagegroup
file split into smaller recipes.

Change-Id: I28ed48fe00dc9cc3875a9029503456af7c4134e6
Signed-off-by: Rogerio Nunes <rogerio.nunes@freescale.com>
packagegroup-fsl: split packagegroup into multiple recipes

A single packagegroup recipe with multiple packagegroups inside
results in the execution of a huge amount of tasks when any image
that includes at least one packagegroup is baked.

This patch splits the packagegroup-fsl recipe into multiple
recipes. As a consequence, only tasks related to recipes
actually used in an image have tasks added to the execution
queue.

Change-Id: I9a8cd438337caa5601fd4e904c76ed2e8b5dca36
Signed-off-by: Rogerio Nunes <rogerio.nunes@freescale.com>
packagegroup-fsl-tools-testapps: Use amd-gpu-x11-bin-mx51 only with X11

Package amd-gpu-x11-bin-mx51 only works if X11 is in
DISTRO_FEATURES, and it should not be installed otherwise.

Change-Id: I526018066de9b7a7d4fd29c65833e5d5d2487884
Signed-off-by: Rogerio Nunes <rogerio.nunes@freescale.com>