layer-management: fix xserver error

* Fix X error of failed request: BadMatch (invalid parameter attributes)
  Major opcode of failed request 62 (X_CopyArea)
  * Use WITH_FORCE_COPY build flag to prevent error.

Signed-off-by: Adrian Alonso <aalonso@freescale.com>
README.mxgal: rename readme file

* Rename file to provide instructions to build against
  FSL MXGAL graphic backed, it uses the distro config
  fsl-ivi-vfb to add mxgal backed support for layer-manager.
* Update layer revision dependencies

Signed-off-by: Adrian Alonso <aalonso@freescale.com>
README.x11: add new file instructions

* Add new file instructions for Genivi BSP support
  for iMX6QSabreAuto using LayerManager X11 backed
  and stock poky-ivi-systemd distro conf file.

Signed-off-by: Adrian Alonso <aalonso@freescale.com>