Realtek switch SoC docs

longan feature OAM

Registers

Offset Name Summary
OAM
7aa4 OAM_PORT_DYING_GASP_CTRL
a120 OAM_CTRL
a124 OAM_PORT_ACT_CTRL
a198 DMY_REG0_OAM
c7bc OAM_GLB_DYING_GASP_CTRL
c7c0 DYING_GASP_POLARITY_CTRL