Instead of resetting flash to 3B address on remove hook, this
implementation only enters 4B mode when needed, which prevents more
unexpected reboot stuck. This implementation makes it only break when
a kernel panic happens during flash operation on 16M+ areas.
Also silent broken-flash-reset warning. We are not dealing with vendors
and it's unpleasant for users to see that unnecessary and long WARN_ON
print.

Signed-off-by: Chuanhong Guo <gch981213@gmail.com>