re: port-amd64/59860: nvmm: support AVX2, AVX512, &c.

Taylor pointed me at
https://www.NetBSD.org/~riastradh/tmp/20260712/nvmmxr0assert.patch
as a real fix, but unfortunately it has made things worse for me:

fatal protection fault in supervisor mode
trap type 4 code 0 rip 0xffffffff8023d36e cs 0x8 rflags 0x10246 cr2 0x743a28a83428 ilevel 0x6 rsp 0xffffba1b8719bd78
curlwp 0xffffb765ba18d800 pid 1590.1786 lowest kstack 0xffffba1b871972c0
panic: trap
cpu3: Begin traceback...
vpanic() at netbsd:vpanic+0x189
panic() at netbsd:panic+0x3c
trap() at netbsd:trap+0xb35
--- trap (number 4) ---
xrstor() at netbsd:xrstor+0xa
nvmm_ioctl() at nvmm:nvmm_ioctl+0xef6
sys_ioctl() at netbsd:sys_ioctl+0x1fa
syscall() at netbsd:syscall+0x9d
--- syscall (number 54) ---

when starting the nvmm VM.


.mrg.