Reland "[lldb][AArch64] Invalidate SVG prior to reconfiguring ZA regdef (#66768)""

This reverts commit 8d80a452.

The pointer to the invalidates lists needs to be non-const. Though in this case
I don't think it's ever modified.

Also I realised that the invalidate list was being set on svg not vg.
Should be the other way around.