staging: rtl8188eu: remove all DBG_88E calls from core/rtw_mlme_ext.c

Remove all DBG_88E calls from core/rtw_mlme_ext.c as this macro is
unnecessary, and many of these calls are dubious in terms of necessity.
Removing all calls will ultimately allow the removal of the macro
itself. Also remove variable declarations for variables which now go
unused as a result of this change with core/rtw_mlme_ext.c
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Link: https://lore.kernel.org/r/20210615001507.1171-4-phil@philpotter.co.ukSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>