Rename msvc build option krb5 to gss

In the MSVC build system we've never separated krb5 from gss,
and always built them both. Since the removal of native krb5
support, this parameter only controls GSSAPI, so rename it
accordingly.

src/tools/msvc/Solution.pm

@@ -219,7 +219,7 @@ s{PG_VERSION_STR "[^"]+"}{__STRINGIFY(x) #x\n#define __STRINGIFY2(z) __STRINGIFY
 			print O "#define HAVE_LIBXSLT\n";
 			print O "#define USE_LIBXSLT\n";
 		}
-		if ($self->{options}->{krb5})
+		if ($self->{options}->{gss})
 		{
 			print O "#define ENABLE_GSS 1\n";
 		}
@@ -494,14 +494,14 @@ sub AddProject
 		$proj->AddIncludeDir($self->{options}->{nls} . '\include');
 		$proj->AddLibrary($self->{options}->{nls} . '\lib\libintl.lib');
 	}
-	if ($self->{options}->{krb5})
+	if ($self->{options}->{gss})
 	{
-		$proj->AddIncludeDir($self->{options}->{krb5} . '\inc\krb5');
-		$proj->AddLibrary($self->{options}->{krb5} . '\lib\i386\krb5_32.lib');
+		$proj->AddIncludeDir($self->{options}->{gss} . '\inc\krb5');
+		$proj->AddLibrary($self->{options}->{gss} . '\lib\i386\krb5_32.lib');
 		$proj->AddLibrary(
-			$self->{options}->{krb5} . '\lib\i386\comerr32.lib');
+			$self->{options}->{gss} . '\lib\i386\comerr32.lib');
 		$proj->AddLibrary(
-			$self->{options}->{krb5} . '\lib\i386\gssapi32.lib');
+			$self->{options}->{gss} . '\lib\i386\gssapi32.lib');
 	}
 	if ($self->{options}->{iconv})
 	{
@@ -621,7 +621,7 @@ sub GetFakeConfigure
 	$cfg .= ' --with-ossp-uuid' if ($self->{options}->{uuid});
 	$cfg .= ' --with-libxml'    if ($self->{options}->{xml});
 	$cfg .= ' --with-libxslt'   if ($self->{options}->{xslt});
-	$cfg .= ' --with-gssapi'    if ($self->{options}->{krb5});
+	$cfg .= ' --with-gssapi'    if ($self->{options}->{gss});
 	$cfg .= ' --with-tcl'       if ($self->{options}->{tcl});
 	$cfg .= ' --with-perl'      if ($self->{options}->{perl});
 	$cfg .= ' --with-python'    if ($self->{options}->{python});