clang-tidy modernize-use-equals-default in comphelper

Change-Id: I24a3ecd2ea9fe7e08c92b95aac57a58b922616b2
Reviewed-on: https://gerrit.libreoffice.org/44054Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

comphelper/source/misc/sharedmutex.cxx

@@ -31,19 +31,6 @@ namespace comphelper
     }
 
 
-    SharedMutex::SharedMutex( const SharedMutex& _rhs )
-        :m_pMutexImpl()
-    {
-        *this = _rhs;
-    }
-
-
-    SharedMutex& SharedMutex::operator=( const SharedMutex& _rhs )
-    {
-        m_pMutexImpl = _rhs.m_pMutexImpl;
-        return *this;
-    }
-
     RefCountedMutex::~RefCountedMutex()
     {
     }

include/comphelper/sharedmutex.hxx

@@ -34,8 +34,6 @@ namespace comphelper
     {
     public:
         SharedMutex();
-        SharedMutex( const SharedMutex& );
-        SharedMutex& operator=( const SharedMutex& );
 
         operator ::osl::Mutex& () { return *m_pMutexImpl; }