Fix omissions in snprintf.c's coverage of standard *printf functions.

A warning on a NetBSD box revealed to me that pg_waldump/compat.c
is using vprintf(), which snprintf.c did not provide coverage for.
This is not good if we want to have uniform *printf behavior, and
it's pretty silly to omit when it's a one-line function.

I also noted that snprintf.c has pg_vsprintf() but for some reason
it was not exposed to the outside world, creating another way in
which code might accidentally invoke the platform *printf family.

Let's just make sure that we replace all eight of the POSIX-standard
printf family.

Also, upgrade plperl.h and plpython.h to make sure that they do
their undefine/redefine rain dance for all eight, not some random
maybe-sufficient subset thereof.

src/pl/plpython/plpython.h

@@ -33,8 +33,14 @@
  * Sometimes python carefully scribbles on our *printf macros.
  * So we undefine them here and redefine them after it's done its dirty deed.
  */
-#undef snprintf
 #undef vsnprintf
+#undef snprintf
+#undef vsprintf
+#undef sprintf
+#undef vfprintf
+#undef fprintf
+#undef vprintf
+#undef printf
 
 #if defined(_MSC_VER) && defined(_DEBUG)
 /* Python uses #pragma to bring in a non-default libpython on VC++ if
@@ -120,15 +126,40 @@ typedef int Py_ssize_t;
 #include <compile.h>
 #include <eval.h>
 
-/* put back our snprintf and vsnprintf */
-#ifdef snprintf
-#undef snprintf
-#endif
+/* put back our *printf macros ... this must match src/include/port.h */
 #ifdef vsnprintf
 #undef vsnprintf
 #endif
-#define vsnprintf				pg_vsnprintf
-#define snprintf				pg_snprintf
+#ifdef snprintf
+#undef snprintf
+#endif
+#ifdef vsprintf
+#undef vsprintf
+#endif
+#ifdef sprintf
+#undef sprintf
+#endif
+#ifdef vfprintf
+#undef vfprintf
+#endif
+#ifdef fprintf
+#undef fprintf
+#endif
+#ifdef vprintf
+#undef vprintf
+#endif
+#ifdef printf
+#undef printf
+#endif
+
+#define vsnprintf		pg_vsnprintf
+#define snprintf		pg_snprintf
+#define vsprintf		pg_vsprintf
+#define sprintf			pg_sprintf
+#define vfprintf		pg_vfprintf
+#define fprintf			pg_fprintf
+#define vprintf			pg_vprintf
+#define printf(...)		pg_printf(__VA_ARGS__)
 
 /*
  * Used throughout, and also by the Python 2/3 porting layer, so it's easier to