rtl8367b: initial support for rtl8367s

rtl8367b: initial support for rtl8367s

From driver point of view no differance between rtl8367b and rtl8367s
if it connected through EXT2 (rgmii only).
So this trivial patch add some identification and initialization only.
SGMII/HSGMII mode for EXT1 is not implemented for the sake of patch
clairity.

Signed-off-by: Serge Vasilugin <vasilugin@yandex.ru>
[Fix code format]
Signed-off-by: DENG Qingfang <dengqf6@mail2.sysu.edu.cn>
[add flags to separate chip_num/chip_id detection; drop error print in
rtl8367b_init_regs, drop unnecessary info prints, code style fixes]
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>