Remove y.tab.h from the beforedepend target.  Also add a rule that shows the dependency of arith_lex.[co] on y.tab.h.
Remove y.tab.h from the beforedepend target.  Also add a
rule that shows the dependency of arith_lex.[co] on y.tab.h.

Suggested by: Bruce Evans <bde@zeta.org.au>

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