Log Message:-----------Improve comment about when to clean generated files.
Modified Files:-------------- pgsql/src/interfaces/ecpg/preproc: Makefile (r1.138 -> r1.139) (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/ecpg/preproc/Makefile?r1=1.138&r2=1.139)
