Skip virNWFilterTechDriver when validating API naming

The virNWFilterTechDriver struct is an internal only driver
API with no public API equivalent. It should be skipped by
the 'check-driverimpls' test case
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

src/check-driverimpls.pl

@@ -68,7 +68,8 @@ while (<>) {
             }
         }
     } elsif (/^(?:static\s+)?(vir(?:\w+)?Driver)\s+/) {
-        next if $1 eq "virNWFilterCallbackDriver";
+        next if $1 eq "virNWFilterCallbackDriver" ||
+                $1 eq "virNWFilterTechDriver";
         $intable = 1;
         $table = $1;
     }