i386: Don't print warning if phys-bits was set automatically

i386: Don't print warning if phys-bits was set automatically

If cpu->host_phys_bits_limit is set, QEMU will make
cpu->phys_bits be lower than host_phys_bits on some cases.  This
triggers a warning that was supposed to be printed only if
phys-bits was explicitly set in the command-line.

Reorder the code so the value of cpu->phys_bits is validated
before the cpu->host_phys_bits handling.  This will avoid
unexpected warnings when cpu->host_phys_bits_limit is set.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20190611205420.20286-1-ehabkost@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>