QtWebEngine build in Qt 5.6 is not allowed for linux imx6 platform

The issue is they were prompted with the “QtWebEngine will not be built” error when building QtWebEngine. I duplicated this issue on Ubuntu 14.04. In Qt5.6, the QtWebEngine build doesn't appear to be allowed for linux-imx6-g++ platform. I used qt-everywhere-enterprise-src-5.6.0-alpha and the toolchain provided.
Below is the configure line used for building Qt 5.6:
configure device imx6 -device-option CROSS_COMPILE=/opt/poky/1.7.1/sysroots/i686-pokysdk-linux/usr/bin/arm-poky-linux-gnueabi/arm-poky-linux-gnueabi -qpa -no-pch -c++11 -opengl es2 -no-xcb -eglfs -sysroot /opt/poky/1.7.1/sysroots/cortexa9hf-vfp-neon-poky-linux-gnueabi -no-gcc-sysroot -no-sse2 -no-sse3 -no-ssse3 -no-sse4.1 -no-sse4.2 -no-avx -no-avx2 -no-mips_dsp -no-mips_dspr2 -no-sql-db2 -no-sql-ibase -no-sql-mysql -no-sql-oci -no-sql-odbc -no-sql-psql -sql-sqlite -icu -force-pkg-config -no-sql-sqlite2 -no-sql-tds -no-cups -no-iconv -no-libudev -qt-pcre -commercial -confirm-license -prefix /usr/local/Qt560
I made the following change to allow the QtWebEngine build for linux imx6 platform in qtwebengine/tools/qmake/mkspecs/features/functions.prf.
Line 17:linux-g+|linux-imx6-g+|win32-msvc2013|macx-clang: return(true)
The build failed due to a missing dependency file atk.pc. Please see below for details. I have checked package libatk1.0-0 was installed on the system, but atk.pc wasn't found on the system.
( test -e Makefile.gyp_run || /home/digia/qt-builds/shadowbuild/qt-5.6.0-alpha/qtbase/bin/qmake /home/digia/qt-source/qt-everywhere-enterprise-src-5.6.0-alpha/qtwebengine/src/core/gyp_run.pro -o Makefile.gyp_run ) && make -f Makefile.gyp_run
….
Updating projects from gyp files...
Package atk was not found in the pkg-config search path.
Perhaps you should add the directory containing `atk.pc'
to the PKG_CONFIG_PATH environment variable
No package 'atk' found
gyp: Call to '../../build/linux/pkg-config-wrapper "/opt/poky/1.7.1/sysroots/cortexa9hf-vfp-neon-poky-linux-gnueabi" "arm" "lib" --cflags atk' returned exit status 1.
Project ERROR: – running gyp_qtwebengine failed –
make[3]: *** [sub-gyp_run-pro-make_first] Error 3
make[3]: Leaving directory `/home/digia/qt-builds/shadowbuild/qt-5.6.0-alpha/qtwebengine/src/core'
make[2]: *** [sub-core-make_first] Error 2
make[2]: Leaving directory `/home/digia/qt-builds/shadowbuild/qt-5.6.0-alpha/qtwebengine/src'
make[1]: *** [sub-src-make_first] Error 2
make[1]: Leaving directory `/home/digia/qt-builds/shadowbuild/qt-5.6.0-alpha/qtwebengine'
make: *** [module-qtwebengine-make_first] Error 2
Is QtWebEngine in Qt 5.6 supported on linux imx6 platform? In addition, can any suggestions on this dependency error and the instructions for building QtWebEngine for embedded Linux be provided?