smp: drop support for deprecated (invalid topologies)

it's was deprecated since 3.1

Support for invalid topologies is removed, the user must ensure
that topologies described with -smp include all possible cpus,
i.e. (sockets * cores * threads) == maxcpus or QEMU will
exit with error.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Acked-by:
Message-Id: <20200911133202.938754-1-imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

docs/system/deprecated.rst

@@ -646,6 +646,19 @@ as ignored. Currently, users are responsible for making sure the backing storage
 specified with ``-mem-path`` can actually provide the guest RAM configured with
 ``-m`` and QEMU fails to start up if RAM allocation is unsuccessful.
 
+``-smp`` (invalid topologies) (removed 5.2)
+'''''''''''''''''''''''''''''''''''''''''''
+
+CPU topology properties should describe whole machine topology including
+possible CPUs.
+
+However, historically it was possible to start QEMU with an incorrect topology
+where *n* <= *sockets* * *cores* * *threads* < *maxcpus*,
+which could lead to an incorrect topology enumeration by the guest.
+Support for invalid topologies is removed, the user must ensure
+topologies described with -smp include all possible cpus, i.e.
+*sockets* * *cores* * *threads* = *maxcpus*.
+
 Block devices
 -------------