LibVT: Rename escape$r to DECSTBM (Set Top and Bottom Margins)

Author: https://github.com/linusg
Commit: 3549623dc6
Pull-request: https://github.com/SerenityOS/serenity/pull/1137
Reviewed-by: https://github.com/awesomekling

Libraries/LibVT/Terminal.h

@@ -167,7 +167,7 @@ private:
     void escape$s(const ParamVector&);
     void escape$u(const ParamVector&);
     void escape$t(const ParamVector&);
-    void escape$r(const ParamVector&);
+    void DECSTBM(const ParamVector&);
     void escape$S(const ParamVector&);
     void escape$T(const ParamVector&);
     void escape$L(const ParamVector&);