Fix SCardHandle on Windows x86_64 for all Card methods.

SCardHandle needs to be the same size as SCardContext which was fixed in the previous commit; it is long on Linux, int32_t on OS X, and DWORD* in Windows.
Fix bug for OS X introduced by 1bd5faa6 (Fix function names in Windows.)

Remove the function mapper when loading the PCSC library on OS X. The ASCII symbol mapper is only needed on Windows and was accidentally also added to Mac.