Fix ipv6 vApp network creation

[adezxc]

Description

This PR fixes bug of not being able to create ipv6 vApp networks, as there was no prefix_length field, only netmask. With the addition of prefix_length, netmask is also marked as Deprecated as `prefix_length is more universal and can be used by both ipv4 and ipv6.

Removes netmask field's Default (255.255.255.0) due to Terraform's limitations when using ExactlyOneOf or ConflictsWith together with Default. Because of this, users will be required to explicitly specify netmask in their .tf files or Terraform will re-create the resource.

All changes are related to resourceVcdVappNetwork

Changes

• Add prefix_length to resourceVcdVappNetwork
• Add ExactlyOneOf to both prefix_length and netmask fields.
• Remove Default value of netmask
• Mark netmask as Deprecated as prefix length is supported by both ipv4 and ipv6.

Testing

• Create TestAccVcdVappNetwork_Isolated_ipv6 to test creation of ipv6 networks.

[vmwclabot]

@adezxc, you must sign every commit in this pull request acknowledging our Developer Certificate of Origin before your changes are merged. This can be done by adding Signed-off-by: John Doe <[email protected]> to the last line of each Git commit message. The e-mail address used to sign must match the e-mail address of the Git author. Click here to view the Developer Certificate of Origin agreement.

• Commit 044a0c2 must be signed by [email protected]

[vmwclabot]

@adezxc, you must sign every commit in this pull request acknowledging our Developer Certificate of Origin before your changes are merged. This can be done by adding Signed-off-by: John Doe <[email protected]> to the last line of each Git commit message. The e-mail address used to sign must match the e-mail address of the Git author. Click here to view the Developer Certificate of Origin agreement.

• Commit 044a0c2 must be signed by [email protected]

[Didainius]

First comments

[adezxc]

Putting this in draft as there is a bug related to updating vApp networks with DHCP.

[vmwclabot]

@adezxc, you must sign every commit in this pull request acknowledging our Developer Certificate of Origin before your changes are merged. This can be done by adding Signed-off-by: John Doe <[email protected]> to the last line of each Git commit message. The e-mail address used to sign must match the e-mail address of the Git author. Click here to view the Developer Certificate of Origin agreement.

• Commit bb6478c must be signed by [email protected]