OImode and TImode moves must be done in XImode to access upper 16
vector registers without AVX512VL. With AVX512VL, we can access
upper 16 vector registers in OImode and TImode.
PR target/89229
* config/i386/i386.md (*movoi_internal_avx): Set mode to XI for
upper 16 vector registers without TARGET_AVX512VL.
(*movti_internal): Likewise.
From-SVN: r268678
