iperf3: upgrade 3.15 -> 3.16

rebase patch 0001-configure.ac-check-for-CPP-prog.patch for iperf3.16

Changelog:
===========
    Multiple test streams started with -P/--parallel will now be
    serviced by different threads. This allows iperf3 to take
    advantage of multiple CPU cores on modern processors, and will
    generally result in significant throughput increases (PR #1591).

    OpenSSL 3 is now detected at build time. If OpenSSL 3 is found,
    various older, deprecated, APIs will not be used. iperf3 will
    continue to work with OpenSSL 1.1.1. OpenSSL is used as a part
    of the iperf3 authentication functionality (Issue #1300, PR#1589).

    The authorized users file used by the authentication functionality
    is now checked for accessibility much earlier during the program
    startup, as opposed to being checked near the start of a test (Issue #1583, PR #1585).

    Iperf3 now requires pthreads and C atomic variables to compile and run.

Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-benchmark/iperf3/iperf3/0001-configure.ac-check-for-CPP-prog.patch

@@ -1,4 +1,4 @@
-From 4801363fbff12bf1019aaf90142981702cecff92 Mon Sep 17 00:00:00 2001
+From 80d208e47a525c915e3961efa61ccf91120ffafa Mon Sep 17 00:00:00 2001
 From: Andrey Zhizhikin <andrey.z@gmail.com>
 Date: Wed, 3 Feb 2021 20:44:34 +0000
 Subject: [PATCH] configure.ac: check for CPP prog
@@ -10,20 +10,19 @@ Absence of check for CPP_PROG causes following build errors:
 
 Upstream-Status: Pending
 Signed-off-by: Andrey Zhizhikin <andrey.z@gmail.com>
-
 ---
  configure.ac | 1 +
  1 file changed, 1 insertion(+)
 
 diff --git a/configure.ac b/configure.ac
-index 53a4db4..3462b3e 100644
+index 2594b39..559b160 100644
 --- a/configure.ac
 +++ b/configure.ac
-@@ -48,6 +48,7 @@ AC_CANONICAL_HOST
+@@ -49,6 +49,7 @@ AC_CANONICAL_HOST
  # Checks for tools: c compiler, ranlib (used for creating static libraries),
  # symlinks and libtool
  AC_PROG_CC
 +AC_PROG_CPP
- AC_PROG_RANLIB
  AC_PROG_LN_S
- LT_INIT
+ 
+ # Add -Wall if we are using GCC.

meta-oe/recipes-benchmark/iperf3/iperf3_3.16.bb

@@ -17,7 +17,7 @@ SRC_URI = "git://github.com/esnet/iperf.git;branch=master;protocol=https \
            file://0001-configure.ac-check-for-CPP-prog.patch \
            "
 
-SRCREV = "917d2f02188f6f4cdc443df7923a4bde72017d92"
+SRCREV = "f9481e1cd35159929458513692e4a8f9fdd1bd6f"
 
 S = "${WORKDIR}/git"