tools/bpf: add unlimited rlimit for flow_dissector_load

On our test machine, bpf selftest test_flow_dissector.sh failed
with the following error:
# ./test_flow_dissector.sh
bpffs not mounted. Mounting...
libbpf: failed to create map (name: 'jmp_table'): Operation not permitted
libbpf: failed to load object 'bpf_flow.o'
./flow_dissector_load: bpf_prog_load bpf_flow.o
selftests: test_flow_dissector [FAILED]

Let us increase the rlimit to remove the above map
creation failure.

Signed-off-by: Yonghong Song <[e-mail]>
Acked-by: Song Liu <[e-mail]>
Signed-off-by: Daniel Borkmann <[e-mail]>

tools/testing/selftests/bpf/flow_dissector_load.c

···
 #include <bpf/bpf.h>
 #include <bpf/libbpf.h>
 
+#include "bpf_rlimit.h"
+
 const char *cfg_pin_path = "/sys/fs/bpf/flow_dissector";
 const char *cfg_map_name = "jmp_table";
 bool cfg_attach = true;