cpu: or1k: drop unused l.swa flag

The "flag" argument isn't set/used in this insn, so drop it.
This fixes an unused variable warning in the generated sim.

cpu/or1korbis.cpu

@@ -717,7 +717,7 @@
      ((MACH ORBIS-MACHS))
      "l.swa ${simm16-split}($rA),$rB"
      (+ OPC_SWA rA rB simm16)
-     (sequence ((SI addr) (BI flag))
+     (sequence ((SI addr))
 	       (set addr (load-store-addr rA simm16-split 4))
 	       (set sys-sr-f (and atomic-reserve (eq addr atomic-address)))
 	       (if sys-sr-f

sim/or1k/sem-switch.c

@@ -1056,7 +1056,6 @@ if (EQSI (ANDSI (tmp_addr, 268435452), CPU (h_atomic_address))) {
 
 {
   SI tmp_addr;
-  BI tmp_flag;
   tmp_addr = or1k32bf_make_load_store_addr (current_cpu, GET_H_GPR (FLD (f_r2)), EXTSISI (FLD (f_simm16_split)), 4);
   {
     USI opval = ANDBI (CPU (h_atomic_reserve), EQSI (tmp_addr, CPU (h_atomic_address)));

sim/or1k/sem.c

@@ -933,7 +933,6 @@ SEM_FN_NAME (or1k32bf,l_swa) (SIM_CPU *current_cpu, SEM_ARG sem_arg)
 
 {
   SI tmp_addr;
-  BI tmp_flag;
   tmp_addr = or1k32bf_make_load_store_addr (current_cpu, GET_H_GPR (FLD (f_r2)), EXTSISI (FLD (f_simm16_split)), 4);
   {
     USI opval = ANDBI (CPU (h_atomic_reserve), EQSI (tmp_addr, CPU (h_atomic_address)));