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 <[email protected]>
Cc: Laszlo Ersek <[email protected]>
Cc: Jordan Justen <[email protected]>
Cc: Eduardo Habkost <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
Reviewed-by: Laszlo Ersek <[email protected]>
Reviewed-by: Eduardo Habkost <[email protected]>
Signed-off-by: Eduardo Habkost <[email protected]>