cmake: new FindQtMobility.cmake

* Add support for QtMobility 1.2 on Maemo 5

Signed-off-by: Corentin Chary <corentin.chary@gmail.com>

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#	modified:   cmake/modules/FindQtMobility.cmake
#	modified:   google/CMakeLists.txt
#	modified:   openstreetmap/CMakeLists.txt
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