target-i386: allow any alignment for SMBASE

target-i386: allow any alignment for SMBASE

Processors up to the Pentium (says Bochs---I do not have old enough
manuals) require a 32KiB alignment for the SMBASE, but newer processors
do not need that, and Tiano Core will use non-aligned SMBASE values.

Reported-by: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>