Avoid timeouts in call-sc.exp

[Michael Chastain]

It's a little weird, but it's much better.

. "synchronize" is spelled with an h.
. include a changelog entry with the submission
. you don't need ${...} for each variable access.
  just $loop_count, $test, and so on.
. this is the fsf version of gdb, it's better to work with
  fsf sources -- either gdb 6.2 or the cvs version of gdb,
  not a red hat gdb.

Can you fix those things up, then download gdb 6.2 or the
cvs version of gdb, and do your work against that.