par-ch9.adb, [...]: Update comments.

par-ch9.adb, [...]: Update comments.

	* par-ch9.adb, sem_aggr.adb, sem_ch3.adb, layout.adb, sem_ch4.adb,
	sem_ch5.adb, sem_mech.adb, exp_util.adb, par-ch10.adb, sem_ch6.adb,
	par-ch11.adb, sem_ch7.adb, par-prag.adb, exp_disp.adb, par-ch12.adb,
	sem_ch8.adb, style.adb, sem_ch9.adb, sem_ch10.adb, prep.adb,
	sem_warn.adb, par-util.adb, scng.adb, sem_eval.adb, checks.adb,
	sem_prag.adb, sem_ch12.adb, styleg.adb, sem_ch13.adb, par-ch3.adb,
	par-tchk.adb, freeze.adb, sfn_scan.adb, par-ch4.adb, sem_util.adb,
	sem_res.adb, par-ch5.adb, lib-xref.adb, sem_attr.adb, par-ch6.adb,
	sem_disp.adb, prepcomp.adb, par-ch7.adb, sem_elab.adb, exp_ch4.adb,
	errout.ads: Update comments. Minor reformatting.

From-SVN: r160979