Fix up ecpg's configuration so it handles "long long int" in MSVC builds.

Although configure-based builds correctly define HAVE_LONG_LONG_INT when
appropriate (in both pg_config.h and ecpg_config.h), builds using the MSVC
scripts failed to do so.  This currently has no impact on the backend,
since it uses that symbol nowhere; but it does prevent ecpg from
supporting "long long int".  Fix that.

Also, adjust Solution.pm so that in the constructed ecpg_config.h file,
the "#if (_MSC_VER > 1200)" covers only the LONG_LONG_INT-related
#defines, not the whole file.  AFAICS this was a thinko on somebody's
part: ENABLE_THREAD_SAFETY should always be defined in Windows builds,
and in branches using USE_INTEGER_DATETIMES, the setting of that shouldn't
depend on the compiler version either.  If I'm wrong, I imagine the
buildfarm will say so.

Per bug #15080 from Jonathan Allen; issue diagnosed by Michael Meskes
and Andrew Gierth.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/151935568942.1461.14623890240535309745@wrigleys.postgresql.org

src/include/pg_config.h.win32

@@ -236,6 +236,11 @@
 /* Define to 1 if `long int' works and is 64 bits. */
 /* #undef HAVE_LONG_INT_64 */
 
+/* Define to 1 if the system has the type `long long int'. */
+#if (_MSC_VER > 1200)
+#define HAVE_LONG_LONG_INT 1
+#endif
+
 /* Define to 1 if `long long int' works and is 64 bits. */
 #if (_MSC_VER > 1200)
 #define HAVE_LONG_LONG_INT_64 1

src/tools/msvc/Solution.pm

@@ -424,10 +424,11 @@ s{PG_VERSION_STR "[^"]+"}{PG_VERSION_STR "PostgreSQL $self->{strver}$extraver, c
 		  || confess "Could not open ecpg_config.h";
 		print $o <<EOF;
 #if (_MSC_VER > 1200)
+#define HAVE_LONG_LONG_INT 1
 #define HAVE_LONG_LONG_INT_64 1
+#endif
 #define ENABLE_THREAD_SAFETY 1
 EOF
-		print $o "#endif\n";
 		close($o);
 	}