net: dsa: lan9303: phy_addr_sel_strap rename and retype

chip->phy_addr_sel_strap is declared as a bool, but is also used as an
integer address base.

Rename 'phy_addr_sel_strap' to 'phy_addr_base', and change type to int.

Signed-off-by: Egil Hjelmeland <privat@egil-hjelmeland.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: lan9303: Protect ALR operations with mutex

ALR table operations are a sequence of related register operations which
should be protected from concurrent access. The alr_cache should also be
protected. Add alr_mutex doing that.

Signed-off-by: Egil Hjelmeland <privat@egil-hjelmeland.no>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: lan9303: Correct register names in comments

Two comments refer to registers, but lack the LAN9303_ prefix.
Fix that.

Signed-off-by: Egil Hjelmeland <privat@egil-hjelmeland.no>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Define eth_stp_addr in linux/etherdevice.h

The lan9303 driver defines eth_stp_addr as a synonym to
eth_reserved_addr_base to get the STP ethernet address 01:80:c2:00:00:00.

eth_reserved_addr_base is also used to define the start of Bridge Reserved
ethernet address range, which happen to be the STP address.

br_dev_setup refer to eth_reserved_addr_base as a definition of STP
address.

Clean up by:
- Move the eth_stp_addr definition to linux/etherdevice.h
- Use eth_stp_addr instead of eth_reserved_addr_base in br_dev_setup.

Signed-off-by: Egil Hjelmeland <privat@egil-hjelmeland.no>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: lan9303: Add STP ALR entry on port 0

STP BPDUs arriving on user ports must sent to CPU port only,
for processing by the SW bridge.

Add an ALR entry with STP state override to fix that.

Signed-off-by: Egil Hjelmeland <privat@egil-hjelmeland.no>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: lan9303: Move struct lan9303 to include/linux/dsa/lan9303.h

The next patch require net/dsa/tag_lan9303.c to access struct lan9303.
Therefore move struct lan9303 definitions from drivers/net/dsa/lan9303.h
to new file include/linux/dsa/lan9303.h.

Signed-off-by: Egil Hjelmeland <privat@egil-hjelmeland.no>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>