Issue #14900: Distuguish call count and primitive call count in pstat output.

Patch by Arne Babenhauserheide.
diff --git a/Lib/pstats.py b/Lib/pstats.py
index 3f0add2..a41962a 100644
--- a/Lib/pstats.py
+++ b/Lib/pstats.py
@@ -165,7 +165,7 @@
               "module"    : (((4, 1),              ), "file name"),
               "name"      : (((6, 1),              ), "function name"),
               "nfl"       : (((6, 1),(4, 1),(5, 1),), "name/file/line"),
-              "pcalls"    : (((0,-1),              ), "call count"),
+              "pcalls"    : (((0,-1),              ), "primitive call count"),
               "stdname"   : (((7, 1),              ), "standard name"),
               "time"      : (((2,-1),              ), "internal time"),
               }