session: make sure fifos are freed on right thread
session: make sure fifos are freed on right thread

Type: improvement

Signed-off-by: Florin Coras <c9715e5cdf0718c2e9b10678757dfb027875eba2@cisco.com>
Change-Id: I3c573641bd95fe899823b66f6c59a2525a18d293

chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,FDio/vpp