wireless: iwlwifi3945/4965 - fix incorrect counting of memory

This patch does fix incorrect counting of memory allocated by kmalloc.
It seems that could lead to allocated memory overrun and corrupt
nearlaid memory area.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Acked-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>