If INSTALL_LIBEXECDIR was set to something != "libexec",
qt-configure-module contained the wrong path to qt-cmake.
Fixes: QTBUG-128137
Pick-to: 6.7 6.5
Change-Id: Ic095ff8cb804bbdd72e238e75ac867b7cc3bd478
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>
(cherry picked from commit 12b0f73a9e9cef35395d0a1560a51604c1c054ff)
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>