Add 'const' to some casts to fix two warnings that are printed by the new gcc (on sparc64).
Add 'const' to some casts to fix two warnings that are printed by the
new gcc (on sparc64).

MFC after:	4 days

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase