insns.dat: fix VFNM instructions incorrectly spelled as VFMN
insns.dat: fix VFNM instructions incorrectly spelled as VFMN

The scalar versions of the VFNM instructions had been incorrectly
spelled VFMN.

projedi/nasm,turingstudio/nasm,projedi/nasm,letolabs/nasm,letolabs/nasm,techkey/nasm,projedi/nasm,techkey/nasm,Distrotech/nasm,turingstudio/nasm,projedi/nasm,Distrotech/nasm,letolabs/nasm,turingstudio/nasm,Distrotech/nasm,Distrotech/nasm,techkey/nasm,projedi/nasm,techkey/nasm,turingstudio/nasm,techkey/nasm