Add Certificate verification support

Call X509_verify_cert to perform the following validations:
      o Check trust settings on the root CA
      o Validity of the certificate chain by
        enabling (X509_V_ERR_CERT_HAS_EXPIRED).
    For details of the verification, refer:
    https://www.openssl.org/docs/manmaster/man1/verify.html

Change-Id: I5fcde5d34658e7b483de2715831107509f31b531
Signed-off-by: Jayanth Othayoth <ojayanth@in.ibm.com>
diff --git a/test/Makefile.am b/test/Makefile.am
index 814966e..279148c 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -18,6 +18,7 @@
     -lstdc++fs \
     $(SDBUSPLUS_LIBS) \
     $(PHOSPHOR_DBUS_INTERFACES_LIBS) \
+    -lssl -lcrypto \
     -lgtest -lgtest_main -lgmock $(PTHREAD_CFLAGS) $(OESDK_TESTCASE_FLAGS)
 
 check_PROGRAMS =
@@ -27,7 +28,7 @@
 
 # Build/add certs_manager_test to test suite
 check_PROGRAMS += certs_manager_test
-certs_manager_test_CPPFLAGS = $(AM_CPPFLAGS) $(GTEST_CPPFLAGS) 
+certs_manager_test_CPPFLAGS = $(AM_CPPFLAGS) $(GTEST_CPPFLAGS)
 certs_manager_test_LDFLAGS = $(AM_LDFLAGS) $(PTHREAD_LIBS) $(OESDK_TESTCASE_FLAGS)
 certs_manager_test_SOURCES = certs_manager_test.cpp
 certs_manager_test_LDADD = $(top_builddir)/certs_manager.o