staging: rtl8188eu: remove all RT_TRACE calls from core/rtw_xmit.c

Remove all RT_TRACE calls from core/rtw_xmit.c as this macro is
unnecessary, and these calls are dubious in terms of necessity.
Removing all calls will ultimately allow the removal of the macro
itself.
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Link: https://lore.kernel.org/r/20210625000756.6313-17-phil@philpotter.co.ukSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>