qt4: add aarch64 support

qt4: add aarch64 support

Add aarch64 support for qt4 packages.

Most of the patches are derived from debian:
http://anonscm.debian.org/cgit/pkg-kde/qt/qt4-x11.git/tree/debian/patches

Add arch check to set right QT_ARCH.

Disable webkit temporarily for qt4 and qt4-embedded that they fail to build:

| runtime/JSValueInlineMethods.h: In constructor
'JSC::JSValue::JSValue(const JSC::JSCell*)':
| runtime/JSValueInlineMethods.h:242:78: error: cast from 'JSC::JSCell*'
to 'int32_t {aka int}' loses precision [-fpermissive]

It has been fix by Qt5, but didn't backport to Qt4. There is an still open
defect for it:
https://bugreports.qt-project.org/browse/QTBUG-35442

Signed-off-by: Kai Kang <kai.kang@windriver.com>