qualcommax: qca-edma: support the kernel 6.18 threaded NAPI API

qualcommax: qca-edma: support the kernel 6.18 threaded NAPI API

dev_set_threaded() takes an enum netdev_napi_threaded on 6.18; it was a
bool before. Select the argument on LINUX_VERSION_CODE so the driver keeps
building on the 6.12 main kernel and on the 6.18 testing kernel.

Without this, the 6.18 testing-kernel build fails with
-Werror=enum-conversion on the threaded-NAPI enable added in commit
98108710b6 ("qualcommax: qca-edma: enable threaded NAPI by default").

Signed-off-by: Julius Bairaktaris <julius@bairaktaris.de>
Link: https://github.com/openwrt/openwrt/pull/24031
Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>