tc-basic-classifier: allow port range for classification

Improve user space class_filter to add port range like:

./class_filter -i red0 --add-port "8080-8082:10:40mbit"
or
./class_filter -i red0 --add-port "8083:20:60mbit"


each port will still be added as individual entry in port map, so no
code change required in bpf side.

Signed-off-by: Vincent Li <vincent.mc.li@gmail.com>

# Please enter the commit message for your changes. Lines starting
# with '#' will be ignored, and an empty message aborts the commit.
#
# Date:      Fri Oct 24 20:58:18 2025 -0700
#
# interactive rebase in progress; onto 5852f61
# Last commands done (2 commands done):
#    pick b69834b tc-basic-classifier: allow port range for classification
#    squash e0f50f6 port range
# No commands remaining.
# You are currently rebasing branch 'main' on '5852f61'.
#
# Changes to be committed:
#	modified:   tc-basic-classifier/class_filter.c
#
# Untracked files:
#	lib/libxdp/#libxdp.3#
#	lib/libxdp/.#libxdp.3
#	lib/libxdp/libxdp.man~
#	tc-basic-classifier/class_filter
#	tc-syncookie/
#	xdp-bench/xdp-bench.8~
#	xdp-filter/xdp-filter.8~
#	xdp-forward/xdp-forward.8~
#	xdp-loader/xdp-loader.8~
#	xdp-monitor/xdp-monitor.8~
#	xdp-trafficgen/xdp-trafficgen.8~
#
