board/keymile/km82xx: setting dip_switch 3 and 4 will run bootloader

Setting dip_switch 3 and 4 also will run bootloader in COGE3 and COGE6
It is required remove local mgmt IP address, when DIP Switch PIN3 is
enabled. DIP Switch 4 also enabled to avoid u-boot update in future
for DIP switch enhancements.

Signed-off-by: Bagavathiannan Palanisamy <Bagavathiannan.Palanisamy@keymile.com>
Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>