Fix whitespace issues

[realJoshByrnes]

This PR fixes 23 out of the 25 whitespace issues in the latest (18.19.0) Asterisk patch.

This PR does not fix the following two whitespace errors, as they are from Asterisk chan_sip#21587 and chan_sip#21589

usecallmanager-patches/asterisk/cisco-usecallmanager-18.19.0.patch:2879: space before tab in indent.
                        ast_cli(a->fd, "  Variables    : ");
usecallmanager-patches/asterisk/cisco-usecallmanager-18.19.0.patch:2882: space before tab in indent.
                                ast_cli(a->fd, "%s%s = %s\n", v != user->chanvars ? "                 " : "", v->name, v->value);

[gareth-palmer]

Looks fine to me.