iwlwifi: mvm: remove redundant define in fw.c

This define is a leftover from dvm (in mvm, it
was replaced by MVM_UCODE_ALIVE_TIMEOUT).

Signed-off-by: Inbal Hacohen <Inbal.Hacohen@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>