wifi: ipw2200: Remove the unused function ipw_alive()

The function ipw_alive() is defined in the ipw2200.c file, but not called
elsewhere, so delete this unused function.

drivers/net/wireless/intel/ipw2x00/ipw2200.c:3007:19: warning: unused function 'ipw_alive'.

Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2410


Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20221017071746.118685-1-jiapeng.chong@linux.alibaba.com