selftests/net/forwarding: Add a test case for tc-flower of mixed port and port-range

After this patch:

 # ./tc_flower_port_range.sh
 TEST: Port range matching - IPv4 UDP                                [ OK ]
 TEST: Port range matching - IPv4 TCP                                [ OK ]
 TEST: Port range matching - IPv6 UDP                                [ OK ]
 TEST: Port range matching - IPv6 TCP                                [ OK ]
 TEST: Port range matching - IPv4 UDP Drop                           [ OK ]

Cc: Qiang Zhang <dtzq01@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20250218043210.732959-3-xiyou.wangcong@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>