mplay32: replace remaining _tcscpy and _stprintf with strsafe functions

The patch replaces the two remaining _tcscpy calls and the two _stprintf calls with calls to
StringCbPrintf and StringCbCopy since they are used anywhere else in the mplay32 source.
It also increases the size of szNewTitle in OpenMciDevice by 128, since the former length is
to small to contain a file name, the application title and some additional chars in every case.