In a Qt build that was configured with INSTALL_MKSPECSDIR set to
something different than INSTALL_DATADIR, the qmake property
QT_HOST_DATA was wrong. Consequently, mkspecs could not be loaded,
rendering qmake dysfunctional.
The reason was that we considered every QT_HOST_xxx property to have the
same value as QT_INSTALL_xxx in a non-cross build.
This is not true for QT_HOST_DATA, because users might want to set
INSTALL_DATADIR to "foo" but INSTALL_MKSPECSDIR to "bar/mkspecs".
Move the unused determination of the host data dir to the QtLibraryInfo
lib and handle QT_HOST_DATA specially.
Fixes: QTBUG-94591
Pick-to: 6.2
Change-Id: I2c44cda8405ff1d14391254fcd1d9b1361cb5855
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
d6e01ae05c