IPACM: fix the fd leaking issue

Fix the fd leaking issue on "resetTetherStats"
and "getStats" APIs.

Change-Id: I131c6ebe1ea1e14194fe4fe019eb21364032e154

ipacm/src/IPACM_OffloadManager.cpp

diff --git a/ipacm/src/IPACM_OffloadManager.cpp b/ipacm/src/IPACM_OffloadManager.cpp
index cf32ff9..c923e2d 100644
--- a/ipacm/src/IPACM_OffloadManager.cpp
+++ b/ipacm/src/IPACM_OffloadManager.cpp
@@ -548,6 +548,7 @@
 	offload_stats.rx = stats.rx_bytes;
 
 	IPACMDBG_H("send getStats tx:%lld rx:%lld \n", offload_stats.tx, offload_stats.rx);
+	close(fd);
 	return SUCCESS;
 }
 
@@ -648,6 +649,7 @@
 		return FAIL_HARDWARE;
 	}
 	IPACMDBG_H("Reset Interface %s stats\n", upstream_name);
+	close(fd);
 	return IPACM_SUCCESS;
 }