iperf3: Update to version 3.12

iperf3: Update to version 3.12

- Update from version 3.10.1 to 3.12
- Update of rootfile not required
- patch to remove pg flag no longer needed. Source code no longer has pg flag set
   in CFLAGS
- Changelog
        iperf-3.12 2022-09-30
            * Notable user-visible changes
              * cJSON has been updated to version 1.7.15 (#1383).
              * The --bind <host>%<dev> option syntax now works properly (#1360 /
                #1371).
              * A server-side file descriptor leak with the --logfile option has
                been fixed (#1369 / #1360 / #1369 / #1389 / #1393).
              * A bug that caused some large values from TCP_INFO to be misprinted
                as negative numbers has been fixed (#1372).
              * Using the -k or -n flags with --reverse no longer leak into future
                tests (#1363 / #1364).
              * There are now various debug level options available with the
                --debug option. These can be used to adjust the amount of
                debugging output (#1327).
              * A new --snd-timeout option has been added to set a termination
                timeout for idle TCP connections (#1215 / #1282).
              * iperf3 is slightly more robust to out-of-order packets during UDP
                connection setup in --reverse mode (#914 / #1123 / #1182 / #1212 /
                #1260).
              * iperf3 will now use different ports for each direction when the
                --cport and --bdir options are set (#1249 / #1259).
              * The iperf3 server will now exit if it can't open its log file
                (#1225 / #1251).
              * Various help message and output fixes have been made (#1299 /
                #1330 / #1345 / #1350).
              * Various compiler warnings have been fixed (#1211 / #1316).
            * Developer-visible changes
              * Operation of bootstrap.sh has been fixed and simplified (#1335 /
                #1325).
              * Flow label support / compatibility under Linux has been improved
                (#1310).
              * Various minor memory leaks have been fixed (#1332 / #1333).
              * A getter/setter has been added for the bind_port parameter
                (--cport option). (#1303, #1305)
              * Various internal documentation improvements (#1265 / #1285 / #1304).
        iperf-3.11 2022-01-31
            * Notable user-visible changes
              * Update links to Discussions in documentation
              * Fix DSCP so that TOS = DSCP * 4 (#1162)
              * Fix --bind-dev for TCP streams (#1153)
              * Fix interface specification so doesn't overlap with IPv6 link-local
                addresses for -c and -B (#1157, #1180)
              * Add get/set test_unit_format function declaration to iperf_api.h
              * Auto adjustment of test-end condition for file transfers (-F), if no end
                condition is set, it will automatically adjust it to file size in bytes
              * Exit if idle time expires waiting for a connection in one-off mode (#1187,
                #1197)
              * Support zerocopy by reverse mode (#1204)
              * Update help and manpage text for #1157, support bind device
              * Consistently print target_bandwidth in JSON start section (#1177)
              * Test bitrate added to JSON output (#1168)
              * Remove fsync call after every write to receiving --file (#1176, #1159)
              * Update documentation for -w (#1175)
              * Fix for #952, different JSON object names for bidir reverse channel

Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Reviewed-by: Peter Müller <peter.mueller@ipfire.org>