pgsql: Back out addition of Win1252 encoding.

Log Message:
-----------
Back out addition of Win1252 encoding.

Modified Files:
--------------
    pgsql/src/backend/utils/mb:
        encnames.c (r1.21 -> r1.22)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mb/encnames.c.diff?r1=1.21&r2=1.22)
    pgsql/src/include/mb:
        pg_wchar.h (r1.55 -> r1.56)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/mb/pg_wchar.h.diff?r1=1.55&r2=1.56)

Removed Files:
-------------
    pgsql/src/backend/utils/mb/Unicode:
        utf8_to_win1252.map
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mb/Unicode/utf8_to_win1252.map)
        win1252_to_utf8.map
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mb/Unicode/win1252_to_utf8.map)
    pgsql/src/backend/utils/mb/conversion_procs/utf8_and_win1252:
        Makefile

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mb/conversion_procs/utf8_and_win1252/Makefile)
        utf8_and_win1252.c

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mb/conversion_procs/utf8_and_win1252/utf8_and_win1252.c)