Remove useless self-assignment of mxImpl->mxAccess

Change-Id: I49fe21ad4a99ea617d6698a9c9eab4daf6fed3b9
Reviewed-on: https://gerrit.libreoffice.org/57951
Tested-by: Jenkins
Reviewed-by: Muhammet Kara <muhammet.kara@pardus.org.tr>

svx/source/dialog/frmsel.cxx

@@ -1023,8 +1023,7 @@ void FrameSelector::SetColorToSelection( const Color& rColor )
 Reference< XAccessible > FrameSelector::CreateAccessible()
 {
     if( !mxImpl->mxAccess.is() )
-        mxImpl->mxAccess = mxImpl->mxAccess =
-            new a11y::AccFrameSelector( *this, FrameBorderType::NONE );
+        mxImpl->mxAccess = new a11y::AccFrameSelector( *this, FrameBorderType::NONE );
     return mxImpl->mxAccess.get();
 }