code following the catch silently ignored some errors; without the
catch they should be thrown like any other tcl error. Also, the
catch used "" instead of {} which meant all the callers who wanted
to include one of the characters "[]$ had to quote it an extra time.
* gdb.base/{callfuncs.exp,commands.exp,gdbvars.exp,printcmds.exp,
ptype.exp,signals.exp,watchpoint.exp}, gdb.c++/{cplusfuncs.exp,
demangle.exp}, gdb.chill/chexp.exp, gdb.fortran/exprs.exp:
Remove extra quoting.
