Line number in route error is incorrect

[Michael Atkins]

The following yaml produces an error during generation, but the wrong line number is reported which means I had to debug this error with gdb and a source build :/

============ BEGIN FILE =====================
network:
  version: 2
  renderer: networkd
  ethernets:
    switch:
      dhcp4: false
      addresses: [ 192.168.50.1/24 ]
      routing-policy:
        - from: 192.168.50.0/24
          table: 128
      routes:
        - to: 0.0.0.0/0
          via: 0.0.0.0
          type: prohibit
          table: 128
          scope: global
        - table: 128
          to: 192.168.50.0/24
          from: 192.168.50.1
          on-link: true
=========== END FILE ===================

The line number in the error reported will be line 12 (the to:0.0.0.0) as shown below:

===================
test.yaml:12:9: Error in network definition: unicast route must include both a 'to' and 'via' IP
        - to: 0.0.0.0/0
        ^
===================

However, this route is actually processed correctly and the error is in the following route starting on line 17.

Perhaps the first parameter to the code:

return yaml_error(node, error, "unicast route must include both a 'to' and 'via' IP");

should be the variable 'entry' rather than 'node'