temporary implementation of LINPTR, FB64 now displays drive number

STATUS.md

@@ -79,7 +79,7 @@ Not all of them - only these we want to have implemented.
 | `$A68E`   | RUNC         | NOT DONE |                                                    |
 | `$A7AE`   | NEWSTT       | NOT DONE |                                                    |
 | `$AB1E`   | STROUT       | DONE     |                                                    |
-| `$BDCD`   | LINPRT       | NOT DONE |                                                    |
+| `$BDCD`   | LINPRT       | DONE     | temporary implementation                           |
 | `$E3BF`   | INIT         | NOT DONE |                                                    |
 | `$E422`   | INITMSG      | DONE     |                                                    |
 | `$E453`   | RVECT        | NOT DONE |                                                    |

c64/basic/bdcd.linprt.s

@@ -7,4 +7,6 @@
 
 
 LINPRT:
-	STUB_IMPLEMENTATION()
+	// XXX This is temporary, to allow some software to work!
+	//     To be replaced by real impleementation.
+	jmp print_integer