vcl svm: fix rx event loss
vcl svm: fix rx event loss

When vcl_epoll_wait_handle_mq handles rx events exceeding maxevents, VPP will not signal because cursize > 0, and the remaining rx events cannot be triggered because the eventfd event has been read. Therefore, we should dequeue all events until cursize = 0. And then handle msg up to maxevents with vcl_epoll_wait_handle_mq_event and those beyond with vcl_handle_mq_event.

Type: fix
Signed-off-by: hanlin <f6f6ab05989e0dc958d3911dc9315d7387f76b5c@163.com>
Change-Id: I8a0c87cb41c837deb8284b40f668cc3c7d9d6e56
Signed-off-by: hanlin <f6f6ab05989e0dc958d3911dc9315d7387f76b5c@163.com>

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