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

Convert the function _rtw_init_xmit_priv() 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.

Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com> # Edimax N150
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20221111083733.3144-4-straube.linux@gmail.com


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