staging: rtl8188eu: rtw_mlme_ext.c: reorder message callbacks and tables

The message handling stored in mlme_sta_tbl and OnAction_tbl are internal and
will be declared static, and their declaration removed from rtw_mlme_ext.h, in
a later commit.

This would break compilation, since they are are referenced before their
definition.

Reorder these functions and the structures that hold them so that symbols are
defined before they are referenced, without the need for forward declarations.

This commit only reorders code, there is no content change.
Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>