[PATCH v2] app/testpmd: fix issue with memory leaks when quit testpmd

[Ke Zhang <ke1x.zhang@intel.com>]

when dpdk is compiled in ASan, there is a memory leaks after
quit testpmd if set mcast_addr, this patch fix this issue.

Error info as following:
ERROR: LeakSanitizer: detected memory leaksDirect leak of
       192 byte(s)
0 0x7f6a2e0aeffe in __interceptor_realloc
	(/lib/x86_64-linux-gnu/libasan.so.5+0x10dffe)
1 0x565361eb340f in mcast_addr_pool_extend
	../app/test-pmd/config.c:5162
2 0x565361eb3556 in mcast_addr_pool_append
	../app/test-pmd/config.c:5180
3 0x565361eb3aae in mcast_addr_add
	../app/test-pmd/config.c:5243

Signed-off-by: Ke Zhang <ke1x.zhang@intel.com>
---
 app/test-pmd/testpmd.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c
index fe2ce19f99..f7e18aee25 100644
--- a/app/test-pmd/testpmd.c
+++ b/app/test-pmd/testpmd.c
@@ -3136,6 +3136,12 @@ close_port(portid_t pid)
 			continue;
 		}
 
+		if (port->mc_addr_nb != 0) {
+			/* free the pool of multicast addresses. */
+			free(port->mc_addr_pool);
+			port->mc_addr_pool = NULL;
+		}
+
 		if (is_proc_primary()) {
 			port_flow_flush(pi);
 			port_flex_item_flush(pi);
-- 
2.25.1