Remove Redundant doDrawBitmap from qsaferenderer.cpp

While checking cachegrind output of the performance test, it turned out that the QSafeRenderer::doDrawBitmap() is not used by the SafeRenderer code anymore; all the bitmaps nowadays are in V3 format and implicitly marked internally as compressed. The performance tests used V3 format bitmap that didn't take advantage of RLE32 compression (and thus was in essense uncompressed) and so used only the doDrawCompressedBitmap() function.

However, tst_qsaferenderer.cpp uses explicitly and implicitly doDrawBitmap() function in several places, so removing the doDrawBitmap() is non-trivial. It is safest to leave the function there for 1.2 even if it breaks the MISRA c++ rule to NOT have used code.

Remember to remove the function and fix the test cases later on.