pgsql-server: Cosmetic improvements/code cleanup: - replace some

Log Message:
-----------
Cosmetic improvements/code cleanup:

- replace some function signatures of the form "some_type foo()" with
"some_type foo(void)"
- replace a few instances of a literal 0 being used as a NULL pointer;
there are more instances of this in the code, but I just fixed a few
- in src/backend/utils/mb/wstrncmp.c, replace K&R style function
declarations with ANSI style, remove use of 'register' keyword
- remove an "extern" modifier that was applied to a function definition
(rather than a declaration)

Modified Files:
--------------
    pgsql-server/src/backend/bootstrap:
        bootparse.y (r1.73 -> r1.74)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/bootstrap/bootparse.y.diff?r1=1.73&r2=1.74)
        bootstrap.c (r1.194 -> r1.195)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/bootstrap/bootstrap.c.diff?r1=1.194&r2=1.195)
    pgsql-server/src/backend/utils/mb:
        wstrncmp.c (r1.6 -> r1.7)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/utils/mb/wstrncmp.c.diff?r1=1.6&r2=1.7)
    pgsql-server/src/backend/utils/misc:
        guc.c (r1.241 -> r1.242)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/utils/misc/guc.c.diff?r1=1.241&r2=1.242)
    pgsql-server/src/bin/initdb:
        initdb.c (r1.59 -> r1.60)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/bin/initdb/initdb.c.diff?r1=1.59&r2=1.60)
    pgsql-server/src/bin/pg_config:
        pg_config.c (r1.7 -> r1.8)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/bin/pg_config/pg_config.c.diff?r1=1.7&r2=1.8)
    pgsql-server/src/bin/pg_ctl:
        pg_ctl.c (r1.32 -> r1.33)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/bin/pg_ctl/pg_ctl.c.diff?r1=1.32&r2=1.33)
    pgsql-server/src/bin/psql:
        common.c (r1.91 -> r1.92)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/bin/psql/common.c.diff?r1=1.91&r2=1.92)
    pgsql-server/src/interfaces/ecpg/preproc:
        descriptor.c (r1.22 -> r1.23)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/interfaces/ecpg/preproc/descriptor.c.diff?r1=1.22&r2=1.23)
        type.c (r1.64 -> r1.65)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/interfaces/ecpg/preproc/type.c.diff?r1=1.64&r2=1.65)
    pgsql-server/src/pl/plpgsql/src:
        pl_funcs.c (r1.37 -> r1.38)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/pl/plpgsql/src/pl_funcs.c.diff?r1=1.37&r2=1.38)