qtbase: add i.MX6UL overrides

This allows to build 'qtbase' for the CC6UL.

It only fixes the broken build, as any QT application that uses OpenGL/ES
will fail because there is no support for QT/OpenGL in modules without
a GPU.

Fix:

arm-dey-linux-gnueabi-g++  -march=armv7-a -mfloat-abi=softfp -mfpu=neon
--sysroot=/ssd/dey/jethro/fb/ccimx6ulsbc/tmp/sysroots/ccimx6ulsbc
-Wl,-O1 -Wl,--hash-style=gnu -Wl,--as-needed -Wl,-O1 -o opengldesktop
opengldesktop.o   -lGL

.../arm-dey-linux-gnueabi/5.2.0/ld: cannot find -lGL

A similar commit was done in meta-fsl-arm.git (branch Krogoth).

https://jira.digi.com/browse/DEL-2607

Signed-off-by: Javier Viguera <javier.viguera@digi.com>

meta-digi-dey/recipes-qt/qt5/qtbase_%.bbappend

@@ -4,6 +4,9 @@ FILESEXTRAPATHS_prepend := "${THISDIR}/${BPN}:"
 
 SRC_URI_append = " file://qt5.sh"
 
+PACKAGECONFIG_GL_mx6ul = "gles2"
+QT_CONFIG_FLAGS_append_mx6ul = "${@base_contains('DISTRO_FEATURES', 'x11', ' -no-eglfs', ' -eglfs', d)}"
+
 PACKAGECONFIG_append = " accessibility examples icu sql-sqlite"
 
 do_install_append() {