examples/l2fwd-keepalive: fix memory leak

Fixes memory leaks detected by Coverity. These are due to ephemeral
memory allocations not being freed when errors occur.

Coverity issue: 127349

Fixes: e2aae1c1ced9 ("ethdev: remove name from extended statistic fetch")

Signed-off-by: Remy Horton <remy.horton@intel.com>

examples/l2fwd-keepalive/shm.c

@@ -80,6 +80,8 @@ struct rte_keepalive_shm *rte_keepalive_shm_create(void)
 				RTE_LOG(INFO, EAL,
 					"Failed to setup SHM semaphore (%s)\n",
 					strerror(errno));
+				munmap(ka_shm,
+					sizeof(struct rte_keepalive_shm));
 				return NULL;
 			}