don't include qconfig.cpp into moc and uic

whatever it was used for is long gone.

Change-Id: Ifab7ae7968b1ab65982b1a6414274b3502bbc3d0
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
suppress error output from pkg-config

under normal circumstances, any errors will be noticed already by the
pkg-config --exists call, which is silent anyway. therefore this doesn't
change anything in normal qmake usage.

however, lupdate's and creator's evaluators skip the --exists calls and
subsequently invoke the normal query, which then prints useless noise to
the terminal.

Task-number: QTBUG-28159
Change-Id: I536412060f3830aafeb0587f855cd6af11227bca
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
TR_EXCLUDE tools including bootstrap lib

there is no point in scanning any of it.

qdoc already excludes itself (and will hopefully move out of qtbase
soon), so not adding it here.

Change-Id: I84356c0988be386de331bb7879b3ebd2108526a2
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
add configure -extprefix option

this adds the possibility to put the actual qt installation outside the
sysroot it is configured for. this makes it possible to install an
x-built qt without "polluting" the sysroot, which makes it possible to
have read-only sysroots, and multiple qt builds for one sysroot.

-prefix is the location within the sysroot as seen by the target itself,
and gets "burned" into QLibraryInfo in QtCore.
-extprefix is the location in the host file system and gets "burned"
into QLibraryInfo in qmake. if it is not specified, it defaults to the
sysrootified prefix, which is the previous behavior.

Task-number: QTBUG-26680
Change-Id: Ia43833c4e27733159afeb8c8b9b2d981378d0cd1
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Integrate device-option into the windows configure

Windows configure does not have -device-option yet.
A hack for android already generated the
qdevice.pri. But it did this even if no android
was build, so merged the device-option with the
android generation of qdevice.pri. The qdevice.pri
is generated earlier in the configure steps than
before to match the linux configure and allow
to set device options before the config.tests
are run.

Change-Id: I753cf0d5eba1479792a685d6e1f5acb38b970893
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>