event/sw: remove unused inflight events count

event/sw: remove unused inflight events count

Reported by clang 13.
This patch removes the inflights variable from the sw_dump function
within the software section of the event driver as it is an unused but
set variable.

Bugzilla ID: 881
Fixes: c66baa68e453 ("event/sw: add dump function for easier debugging")
Cc: stable@dpdk.org
Reported-by: Liang Longfeng <longfengx.liang@intel.com>
Signed-off-by: Conor Walsh <conor.walsh@intel.com>
Acked-by: Harry van Haaren <harry.van.haaren@intel.com>
Reviewed-by: David Marchand <david.marchand@redhat.com>