Hardware: Extend network interface description

Make it clear which Linux interface belongs to which connector.

Signed-off-by: Stefan Wahren <stefan.wahren@chargebyte.com>

Author: lategoodbye

docs/source/hardware.rst

@@ -59,6 +59,10 @@ Power & Safety
 Profinet
 ^^^^^^^^
 
+The Profinet interface supports 10/100 Mbit/s Ethernet. In the Linux operating
+system it is available as network interface ``eth2``. The MAC address of this
+interface is stored within the OTP of the System on Chip.
+
 .. list-table::
    :widths: 15 85
    :header-rows: 1
@@ -81,6 +85,10 @@ Profinet
 LAN (OCPP)
 ^^^^^^^^^^
 
+The LAN interface supports 10/100 Mbit/s Ethernet. In the Linux operating
+system it is available as network interface ``eth0``. The MAC address of this
+interface is stored within the OTP of the System on Chip.
+
 .. list-table::
    :widths: 15 85
    :header-rows: 1
@@ -103,6 +111,10 @@ LAN (OCPP)
 MCS
 ^^^
 
+The MCS interface supports 10 Mbit/s Ethernet. In the Linux operating
+system it is available as network interface ``eth1``. The MAC address of
+this host interface is stored within the EEPROM on the Charge SOM.
+
 .. list-table::
    :widths: 15 85
    :header-rows: 1
@@ -133,6 +145,10 @@ MCS
 IO
 ^^
 
+The CAN interface is a full implementation of the CAN FD protocol specification
+version 2.0B. It is available on Linux network interface ``can0``, which has a
+default bitrate of 1 Mbit/s.
+
 .. list-table::
    :widths: 15 85
    :header-rows: 1