net/bnxt: fix data type for vnic attributes entry size
net/bnxt: fix data type for vnic attributes entry size

Prevent the arithmetic in bnxt_alloc_vnic_attributes from causing
any unintentional havoc because of the usage of a signed variable.

Coverity issue: 137874

Signed-off-by: Ajit Khaparde <01965fbd61169dc18f3fb5e13de7f67d298f8924@broadcom.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk