nrf51: Add new HWID 0x008F

Add new entry in nrf51_known_devices_table for nRF51822 chip found on
chinese Core51822 dev board. The chp has markings N51822 / QFAAH1 / 1630FW
Nordic Semiconductor nRF51 Series Compatibility matrix confirms that this chip
has 256K Flash and 16K RAM.

Change-Id: I571d15913c6f6e02a6f09c883d7dfc5a66b57c28
Signed-off-by: Damyan Mitev <damyan_mitev@mail.bg>
Reviewed-on: http://openocd.zylin.com/4091


Tested-by: jenkins
Reviewed-by: Freddie Chopin <freddie.chopin@gmail.com>