Update handling of macro __assign_str() to also support the one-argument
variant when building against kernel 6.10 or later. This is needed for
building the next LTS kernel 6.12.
Fixes: 384d079fd8 ("mac80211: update to version 6.11")
Signed-off-by: Tony Ambardar <itugrok@yahoo.com>
Link: https://github.com/openwrt/openwrt/pull/17456
Signed-off-by: Robert Marko <robimarko@gmail.com>