Drop the "accel" property from MachineState, and instead desugar
"-machine accel=" to a list of "-accel" options.
This has a semantic change due to removing merge_lists from -accel.
For example:
- "-accel kvm -accel tcg" all but ignored "-accel kvm". This is a bugfix.
- "-accel kvm -accel thread=single" ignored "thread=single", since it
applied the option to KVM. Now it fails due to not specifying the
accelerator on "-accel thread=single".
- "-accel tcg -accel thread=single" chose single-threaded TCG, while now
it will fail due to not specifying the accelerator on "-accel
thread=single".
Also, "-machine accel" and "-accel" become incompatible.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
6f6e1698a6