This fixes the following crash, introduced by commit
49d2e648e8:
$ gdb --args qemu-system-x86_64 -machine pc,mem-merge=off -object memory-backend-ram,id=ram-node0,size=1024
[...]
Program received signal SIGABRT, Aborted.
(gdb) bt
#0 0x00007ffff253b8c7 in raise () at /lib64/libc.so.6
#1 0x00007ffff253d52a in abort () at /lib64/libc.so.6
#2 0x00007ffff253446d in __assert_fail_base () at /lib64/libc.so.6
#3 0x00007ffff2534522 in () at /lib64/libc.so.6
#4 0x00005555558bb80a in qemu_opt_get_bool_helper (opts=0x55555621b650, name=name@entry=0x5555558ec922 "mem-merge", defval=defval@entry=true, del=del@entry=false) at qemu/util/qemu-option.c:388
#5 0x00005555558bbb5a in qemu_opt_get_bool (opts=<optimized out>, name=name@entry=0x5555558ec922 "mem-merge", defval=defval@entry=true) at qemu/util/qemu-option.c:398
#6 0x0000555555720a24 in host_memory_backend_init (obj=0x5555562ac970) at qemu/backends/hostmem.c:226
Instead of using qemu_opt_get_bool(), that didn't work with
qemu_machine_opts for a long time, we can use the corresponding
MachineState fields.
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>