[binutils-gdb] Use TRY/CATCH in remove_prev_frame

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT 09a5e1b570eefbc029939fd43c99152996060d95 ***

Author: Tom Tromey <tom@tromey.com>
Branch: master
Commit: 09a5e1b570eefbc029939fd43c99152996060d95

Use TRY/CATCH in remove_prev_frame

This changes remove_prev_frame to use TRY/CATCH instead of a cleanup.
TRY/CATCH seemed appropriate here because the cleanup is only needed
in the case where an exception is thrown.

Tested by the buildbot.

ChangeLog
2018-05-25  Tom Tromey  <tom@tromey.com>

	* frame.c (remove_prev_frame): Remove.
	(get_prev_frame_if_no_cycle): Use TRY/CATCH.