Avoid warning when compilation with MSVC2013

warning: C4005: 'va_copy' : macro redefinition

Change-Id: Ib2bfd2229cb3ae00e084dd6df7a4558a5a766d55
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>