staging: r8188eu: convert ODM_ReadAndConfig_MAC_REG_8188E() to int

staging: r8188eu: convert ODM_ReadAndConfig_MAC_REG_8188E() to int

The function ODM_ReadAndConfig_MAC_REG_8188E() has return type
'enum HAL_STATUS'. Convert the return type to int and use common
kernel error logic. Return 0 on success and negative values on
failure. The goal is to get rid of enum HAL_STATUS in the end.

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/20220928144323.13164-2-straube.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>