Only try to duplicate internal_data if it is non-NULL.
Only try to duplicate internal_data if it is non-NULL.

Pointed out by clang.

Signed-off-by: Chris Lalancette <60b62644009db6b194cc0445b64e9b27bb26433a@redhat.com>

ike-dai/libdeltacloud-for-cloudmodule,ike-dai/libdeltacloud-for-cloudmodule