qtwrapper: Resolve type discrepancy in fileTransferInfo.

* src/qtwrapper/configurationmanager_wrap.h (fileTransferInfo)
<int64_t&>: Change type of TOTAL and PROGRESS to qlonglong&.  Convert
to int64_t via reinterpret_cast.  This is safe as both types are
guaranteed to be 64 bits.

Change-Id: I91d7e12e751ef5e4d07ac4647b4e99a15b05b507