Fix regex for DCQCN

[velomatt]

• skip task if regex does not match
• won't fail if the regex doesn't match now

[velomatt]

Low risk changes. Only applies to configure_vlans play.

Was previously failing when attempting to configure a host with ConnectX 4 adapters. Now those adapters will be skipped and not fail with a cryptic error.

[mssawant]

@velomatt , trying to understand the problem and the solution, since we needed to add the connectX-4 adapters before, why are we silently skipping them now?

[suggestion] I think, Was previously failing when attempting to configure a host with ConnectX 4 adapters. Now those adapters will be skipped and not fail with a cryptic error. would help to be part of the commit message problem statement.

[velomatt]

@velomatt , trying to understand the problem and the solution, since we needed to add the connectX-4 adapters before, why are we silently skipping them now?

[suggestion] I think, Was previously failing when attempting to configure a host with ConnectX 4 adapters. Now those adapters will be skipped and not fail with a cryptic error. would help to be part of the commit message problem statement.

This bugfix is not specific to ConnectX 4 adapters, I'm just giving an example of where I encountered this error. This error can potentially happen with any Mellanox adapter if it does not have the specific DCQCN parameters we are tuning for maximum performance.

[snubatreus]

Looks good 👍