ipmi:ssif: make ssif_i2c_send() void

This function actually needs no return value. So remove the unneeded
check and make it void.

Signed-off-by: Liguang Zhang <zhangliguang@linux.alibaba.com>
Message-Id: <20210301140515.18951-1-zhangliguang@linux.alibaba.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>