VPP-API: Cancel timeout thread without sending READ_TIMEOUT message.
VPP-API: Cancel timeout thread without sending READ_TIMEOUT message.

This caused a spurious message to be sent on the API ring causing debug messages.

Change-Id: Ief4ca655ae048aad386a88fed11e8c1114378dc7
Signed-off-by: Ole Troan <aeed71d78dc09e4764ceac69b111eee9b50cfdd0@cisco.com>

vpp-dev/vpp,FDio/vpp,FDio/vpp,vpp-dev/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,vpp-dev/vpp,vpp-dev/vpp,vpp-dev/vpp,chrisy/vpp,vpp-dev/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,vpp-dev/vpp,chrisy/vpp,FDio/vpp