wifi: mwifiex: handle possible mwifiex_write_reg() errors

Return -1 on possible 'mwifiex_write_reg()' errors in
'mwifiex_init_sdio_ioport()', do not ignore the value
returned by the latter in 'mwifiex_init_sdio()' and
'mwifiex_sdio_up_dev()' as well.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Acked-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230802160726.85545-4-dmantipov@yandex.ru