net: vmxnet: use g_new for pkt initialisation

net: vmxnet: use g_new for pkt initialisation

When vmxnet transport abstraction layer initialises pkt,
the maximum fragmentation count is not checked. This could lead
to an integer overflow causing a NULL pointer dereference.
Replace g_malloc() with g_new() to catch the multiplication
overflow.

Reported-by: Li Qiang <liqiang6-s@360.cn>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Acked-by: Dmitry Fleytman <dmitry@daynix.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>