wifi: iwlwifi: mvm: initialize seq variable

wifi: iwlwifi: mvm: initialize seq variable

Clang static analysis reports this issue
d3.c:567:22: warning: The left operand of '>' is
  a garbage value
  if (seq.tkip.iv32 > cur_rx_iv32)
      ~~~~~~~~~~~~~ ^

seq is never initialized. Call ieee80211_get_key_rx_seq() to
initialize seq.

Fixes: 0419e5e672d6 ("iwlwifi: mvm: d3: separate TKIP data from key iteration")
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230414130637.6dd372f84f93.If1f708c90e6424a935b4eba3917dfb7582e0dd0a@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>