staging: r8188eu: convert rtw_writeN() to common error logic

Convert the function rtw_writeN() away from returning _FAIL or
_SUCCESS which uses inverted error logic. Use the common error logic
instead. Return 0 for success and negative values for failure.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com> # Edimax N150
Link: https://lore.kernel.org/r/20230108123804.3754-1-straube.linux@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>