LibVT: Add stubs for DECPNM, DECPAM

Still not implemented, but provides easier to grasp FIXMEs.

Userland/Libraries/LibVT/Terminal.cpp

@@ -953,6 +953,16 @@ void Terminal::DECDC(Parameters params)
         scroll_left(row, cursor_column(), num);
 }
 
+void Terminal::DECPNM()
+{
+    dbgln("FIXME: implement setting the keypad to numeric mode");
+}
+
+void Terminal::DECPAM()
+{
+    dbgln("FIXME: implement setting the keypad to application mode");
+}
+
 void Terminal::DSR(Parameters params)
 {
     if (params.size() == 1 && params[0] == 5) {
@@ -1077,6 +1087,12 @@ void Terminal::execute_escape_sequence(Intermediates intermediates, bool ignore,
         case '9':
             DECFI();
             return;
+        case '=':
+            DECPAM();
+            return;
+        case '>':
+            DECPNM();
+            return;
         }
     } else if (intermediates[0] == '#') {
         switch (last_byte) {

Userland/Libraries/LibVT/Terminal.h

@@ -361,6 +361,12 @@ protected:
     // DECDC - Delete Column
     void DECDC(Parameters);
 
+    // DECPNM - Set numeric keypad mode
+    void DECPNM();
+
+    // DECPAM - Set application keypad mode
+    void DECPAM();
+
 #ifndef KERNEL
     TerminalClient& m_client;
 #else