insns.dat: Fix SHA256RNDS2 optional xmm0 argument
insns.dat: Fix SHA256RNDS2 optional xmm0 argument

In commit 1eef781594b08a7f we allowed xmm0
to be implicit, then in dcaef4b09502aae7 it
occasionally got ripped off. Move it back.

https://bugzilla.nasm.us/show_bug.cgi?id=3392379

Reported-by: ig <345675c7048bdfd2ae51c5abbc133b36e3e6b0f8@avast.com>
Signed-off-by: Cyrill Gorcunov <7a1ea01eee6961eb1e372e3508c2670446d086f4@gmail.com>

techkey/nasm,techkey/nasm,techkey/nasm,techkey/nasm,techkey/nasm