Rollup merge of #145017 - pmur:murp/s390x-improve-asm-test, r=nnethercote

Explicitly disable vector feature on s390x baseline of bad-reg test

If the baseline s390x cpu is changed to a newer variant, such as z13, the vector feature may be enabled by default. When rust is packaged on fedora 38 and newer, it is set to z13.

Explicitly disable vector support on the baseline test for consistent results across s390x cpus.

Author: Zalathar