pgsql-server: Remove some long-obsolete code that was causing a strange

Log Message:
-----------
Remove some long-obsolete code that was causing a strange error message
when someone attempts to create a column of a composite datatype.  For
now, just make sure we produce a reasonable error at the 'right place'.
Not sure if this will be made to work before 7.5, but make it act
reasonably in case nothing more gets done.

Modified Files:
--------------
    pgsql-server/src/backend/catalog:
        heap.c (r1.266 -> r1.267)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/catalog/heap.c.diff?r1=1.266&r2=1.267)
    pgsql-server/src/backend/parser:
        analyze.c (r1.302 -> r1.303)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/parser/analyze.c.diff?r1=1.302&r2=1.303)