include USER-SDPD package in list of user packages in conventional make

src/Makefile

@@ -63,7 +63,7 @@ PACKUSER = user-atc user-awpmd user-bocs user-cgdna user-cgsdk user-colvars \
 	   user-mgpt user-misc user-mofff user-molfile \
 	   user-netcdf user-omp user-phonon user-ptm user-qmmm user-qtb \
 	   user-quip user-reaxc user-scafacos user-smd user-smtbq \
-	   user-sph user-tally user-uef user-vtk
+	   user-sdpd user-sph user-tally user-uef user-vtk
 
 PACKLIB = compress gpu kim kokkos latte meam message mpiio mscg poems \
 	  python reax voronoi \