Failed to load "vxlapi" dll

On 64 bit systems the api dll from vector has the name vxlapi64.dll and trying to load the 32 bit dll fails. A possible solution could be to try to load also the 64bit dll if the first one fails.

Filename: vectorcan_symbols_p.h
Function: inline bool resolveSymbols(QLibrary *vectorcanLibrary)
Fix proposal: please see attached file.