gdb/465: replace selected_frame with get_selected_frame()

[cagney@redhat.com]

Synopsis: replace selected_frame with get_selected_frame()

Responsible-Changed-From-To: unassigned->cagney
Responsible-Changed-By: cagney
Responsible-Changed-When: Mon Jan 13 12:56:08 2003
Responsible-Changed-Why:
    mine
State-Changed-From-To: open->closed
State-Changed-By: cagney
State-Changed-When: Mon Jan 13 12:56:08 2003
State-Changed-Why:
    Replaced.  Global variable deprecated.

http://sources.redhat.com/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gdb&pr=465