[c-nsp] CSCuy29638 - MPLS (for IPv4) Brokenness Fixed - ASR920

[Mark Tinka]

Hi all.

Just to confirm that the newly-released 15.5(3)S3a / 3.16(3a)S contains
the fix for CSCuy29638.

CSCuy29638 is the bug where MPLS labels above the 400,000 range causes a
corruption of the payload, leading to a breakage in IPv4 traffic from
being forwarded by the ASR920.

I've upgraded an ASR920 that is affected by this and confirm the issue
is now fixed.

I'd recommend anyone running an ASR920, particularly one adjacent to a
Junos-based device, upgrades to this code to avoid pain.

Mark.