wifi: iwlwifi: cfg: remove trailing dash from FW_PRE constants

wifi: iwlwifi: cfg: remove trailing dash from FW_PRE constants

We have the trailing dash here, but that complicates all
the code. Simplify this by removing the dashes, adding
them to the *_MODULE_FIRMWARE macros, and adjusting the
code using this accordingly.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230621130443.72240ca13b83.I1f4ed547f0964719ed98a3ef928080462d594491@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>