• Allow for VLAN-sized frames and set IFCAP_VLAN_MTU.
• On resume all registers have to be initialized again like after power-on so reset sc_inited in gem_suspend() in order get all of the registers set next time gem_init_regs() is called.
• On at least some ERI and GEM revisions GEM_MAC_RX_OVERFLOW happen often due to a silicon bug and re-initializing is all we can do about these errors so make handling them non-verbose.
• Remove a superfluous memset(3) call in gem_meminit(), all elements are initialized to 0 anyway.

MFC after: 1 week