net/ice/base: add sibling head to parse nodes

net/ice/base: add sibling head to parse nodes

There was a bug in the previous code which never traverses all the
children to get the first node of the requested layer.

Added a sibling head pointer to point the first node of each layer
per TC. This helps the traverse easy and quicker and also removed the
recursive, complexity of the code.

Signed-off-by: Victor Raj <victor.raj@intel.com>
Signed-off-by: Paul M Stillwell Jr <paul.m.stillwell.jr@intel.com>
Signed-off-by: Leyi Rong <leyi.rong@intel.com>
Acked-by: Qi Zhang <qi.z.zhang@intel.com>