Resolve a number of compilation issues with INTEGRITY

Resolve a number of compilation issues with INTEGRITY

First, #ifdef'ed out getpwuid_r() and getpwgid_r() usage since users/groups support is not in in single-process Posix mode.
Also, correct a typo and add missing files to io.pri.
Update documentation to disable libtiff which won't compile until ibtiff itself is updated, and add back -no-exceptions in the sample command line. And add a line to compile host tools.
Add a dummy QT_OPEN_LARGEFILE definition in qplatformdefs.h since there is code that requires it.
Move definition of getGlyph() after the definition of qHash(GlyphAndSubPixelPosition).

Merge-request: 2686
Reviewed-by: ossi
(cherry picked from commit 8fe04a14b1f3688c9ce0933ebec0c28616595d93)
Change-Id: I8fe04a14b1f3688c9ce0933ebec0c28616595d93
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@nokia.com>