pgsql: Applied Zoltan's patch to make char the default sqlda type.

Log Message:
-----------
Applied Zoltan's patch to make char the default sqlda type.

Given that undefined types are handled as character strings anyway the type
translation function can simply return the correcponding ECPGt_char type.

Modified Files:
--------------
    pgsql/src/interfaces/ecpg/ecpglib:
        typename.c (r1.17 -> r1.18)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/ecpg/ecpglib/typename.c?r1=1.17&r2=1.18)