Fix name for PyDateTime_FromDateAndTime.

Closes bug #1124278.

Doc/api/concrete.tex

@@ -2793,7 +2793,7 @@ Macros to create objects:
   \versionadded{2.4}
 \end{cfuncdesc}
 
-\begin{cfuncdesc}{PyObject*}{PyDate_FromDateAndTime}{int year, int month,
+\begin{cfuncdesc}{PyObject*}{PyDateTime_FromDateAndTime}{int year, int month,
         int day, int hour, int minute, int second, int usecond}
   Return a \code{datetime.datetime} object with the specified year, month,
   day, hour, minute, second and microsecond.