net/ena: fix build for O1 optimization
net/ena: fix build for O1 optimization

Can be reproduced with "make EXTRA_CFLAGS='-O1'" command using
gcc (GCC) 9.3.1 20200408 (Red Hat 9.3.1-2)

Build error:
.../drivers/net/ena/ena_ethdev.c: In function ‘eth_ena_dev_init’:
.../drivers/net/ena/ena_ethdev.c:1815:20:
    error: ‘wd_state’ may be used uninitialized in this function
           [-Werror=maybe-uninitialized]
 1815 |  adapter->wd_state = wd_state;
      |  ~~~~~~~~~~~~~~~~~~^~~~~~~~~~

This looks like false positive, fixing by assigning initial value to
'wd_state' variable.

Signed-off-by: Ferruh Yigit <ba8734c3c506d2e3557bd4ac8fdaccd25bdb9aa7@intel.com>
Acked-by: Michal Krawczyk <a91dcbb4df49d8bfe0a9930d7ff911a4292ca1f5@semihalf.com>

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