Fix agl IC demo is not show both screen

Fix agl IC demo is not show both screen

In R-Car platform such as ref-hw is not show cluster and ivi screen.
It cause by installing gles-user-module-firmware into guest image.
gles-user-module-firmware is installed by kernel-module-gles dependency.
kernel-module-gles is installed by MACHINE_EXTRA_RRECOMMENDS from agl_rcar.inc,
but this environment variable can't delete in guest build.

This patch fix this issue.

Bug-AGL: SPEC-4888

Change-Id: Ica0f8d6ef48d30333bbccdff7380471b11ad063c
Signed-off-by: Naoto Yamaguchi <naoto.yamaguchi@aisin.co.jp>
(cherry picked from commit 452232c0acd8753bc70aa0af04171f606e132be0)