Fix minor grammar typo.

Doc/whatsnew/whatsnew24.tex

@@ -1365,7 +1365,7 @@ Changes to Python's build process and to the C API include:
   switch enables profiling using the Pentium's Time-Stamp-Counter
   register.  The switch is slightly misnamed, because the profiling
   feature also works on the PowerPC platform, though that processor
-  architecture doesn't called that register the TSC.
+  architecture doesn't call that register a TSC.
    
   \item The \ctype{tracebackobject} type has been renamed to \ctype{PyTracebackObject}.