Wlanstat has a uncommon version of BSD-2-Clause. This one is more familiar under /sys and has many different SPDX-License-Identifier-tag.
Some random file from grep for examples under /sys/:
sys/crypto/openssl/ossl_arm.h: * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
sys/dev/mwl/if_mwlioctl.h: * SPDX-License-Identifier: BSD-2-Clause
sys/dev/wtap/wtap_hal/hal.h: * SPDX-License-Identifier: BSD-2-Clause
sys/dev/wtap/wtap_hal/hal.c: * SPDX-License-Identifier: BSD-2-Clause
I've used this grep to find files: grep -rl 'similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any' * | xargs grep "SPDX"
There is similar BSD-3-Clause license available: BSD-3-Clause-acpica
Most common SPDX tag for this one under /sys is BSD-2-Clause but I for example scancode-toolkit has LicenseRef-scancode-intel-bsd-2-clause which has same wording as this license.
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