target-ppc: Bug in BookE wait instruction

Fixed bug in code generation for the PowerPC "wait" instruction. It
doesn't make sense to store a non-initialized register.
Signed-off-by: NJakub Horak <thement@ibawizard.net>
[dwg: revised commit message]
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

target-ppc/translate.c

@@ -3499,7 +3499,7 @@ static void gen_sync(DisasContext *ctx)
 /* wait */
 static void gen_wait(DisasContext *ctx)
 {
-    TCGv_i32 t0 = tcg_temp_new_i32();
+    TCGv_i32 t0 = tcg_const_i32(1);
     tcg_gen_st_i32(t0, cpu_env,
                    -offsetof(PowerPCCPU, env) + offsetof(CPUState, halted));
     tcg_temp_free_i32(t0);