Fix endptr output value in android_wcstoxxx()

These functions incorrectly multiplied an increment of wchar_t pointer
by sizeof(wchar_t), which made the result quite wrong, so just don't do
this.

See 744ea8a618 (For Android (wxQT), add private wcstol, wcstoul and
wcstod, 2015-02-11).

src/common/wxcrt.cpp

@@ -1256,7 +1256,7 @@ int wxVsscanf(const wxCStrData& str, const wchar_t *format, va_list ap)
 #define ANDROID_WCSTO_END \
     if(endptr) { \
         if(dstendp) \
-            *endptr = (wchar_t*)(nptr + (dstendp - dst) * sizeof(wchar_t)); \
+            *endptr = (wchar_t*)(nptr + (dstendp - dst)); \
         else \
             *endptr = NULL; \
     } \