For 4.11, the SMP option is --enable-experimental-smp

OAR/contrib/build.rtems.4.11.2.smp.sh

@@ -105,7 +105,7 @@ BUILD_LOG=~/rtems.build.logs/${DATE}.log
     ../rtems-git/configure \
         --target=sparc-rtems4.11 --prefix=${RTPREFIX} \
         --enable-rtemsbsp="leon2 leon3 ngmp" --enable-posix \
-        --enable-cxx --enable-networking --enable-smp
+        --enable-cxx --enable-networking --enable-experimental-smp
     make all
     make install
 } |& tee ${BUILD_LOG}