build: exclude the escape sequences for F13...F16 from the tiny version

The F13 to F16 function keys are no longer bound by default, and when
there is no nanorc file, there is no way to bind them, so there is no
point in recognizing their escape sequences.

src/winio.c

@@ -818,11 +818,13 @@ int convert_sequence(const int *seq, size_t length, int *consumed)
 					case 'D': /* Esc O 1 ; 2 D == Shift-Left on Terminal. */
 						shift_held = TRUE;
 						return arrow_from_ABCD(seq[4]);
+#ifdef ENABLE_NANORC
 					case 'P': /* Esc O 1 ; 2 P == F13 on Gnome Terminal. */
 					case 'Q': /* Esc O 1 ; 2 Q == F14 on Gnome Terminal. */
 					case 'R': /* Esc O 1 ; 2 R == F15 on Gnome Terminal. */
 					case 'S': /* Esc O 1 ; 2 S == F16 on Gnome Terminal. */
 						return KEY_F(13 + seq[4] - 'P');
+#endif
 				}
 				break;
 			case '5':
@@ -844,12 +846,14 @@ int convert_sequence(const int *seq, size_t length, int *consumed)
 					case '2':
 						if (length > 2) {
 							*consumed = 3;
+#ifdef ENABLE_NANORC
 							if ('O' < seq[2] && seq[2] < 'T')
 								/* Esc O 2 P == F13 on Konsole. */
 								/* Esc O 2 Q == F14 on Konsole. */
 								/* Esc O 2 R == F15 on Konsole. */
 								/* Esc O 2 S == F16 on Konsole. */
 								return KEY_F(13 + seq[2] - 'P');
+#endif
 						}
 						break;
 					case '5':
@@ -977,6 +981,8 @@ int convert_sequence(const int *seq, size_t length, int *consumed)
 						return SHIFT_END;
 					case 'H': /* Esc [ 1 ; 2 H == Shift-Home on xterm. */
 						return SHIFT_HOME;
+#endif
+#ifdef ENABLE_NANORC
 					case 'P': /* Esc [ 1 ; 2 P == F13 on xterm. */
 					case 'Q': /* Esc [ 1 ; 2 Q == F14 on xterm. */
 					case 'R': /* Esc [ 1 ; 2 R == F15 on xterm. */
@@ -1064,15 +1070,20 @@ int convert_sequence(const int *seq, size_t length, int *consumed)
 								case '1': /* Esc [ 2 1 ~ == F10 on the same. */
 									return KEY_F(10);
 								case '3': /* Esc [ 2 3 ~ == F11 on the same. */
+									return KEY_F(11);
 								case '4': /* Esc [ 2 4 ~ == F12 on the same. */
+									return KEY_F(12);
+#ifdef ENABLE_NANORC
 								case '5': /* Esc [ 2 5 ~ == F13 on VT220/VT320/
 										   * Linux console/rxvt/Eterm. */
+									return KEY_F(13);
 								case '6': /* Esc [ 2 6 ~ == F14 on the same. */
-									return KEY_F(11 + seq[2] - '3');
+									return KEY_F(14);
 								case '8': /* Esc [ 2 8 ~ == F15 on the same. */
 									return KEY_F(15);
 								case '9': /* Esc [ 2 9 ~ == F16 on the same. */
 									return KEY_F(16);
+#endif
 							}
 						} else if (length > 2 && seq[2] == '~')
 							/* Esc [ 2 ~ == Insert on VT220/VT320/