Modify the RoCC interface to include status in the command queue. (#41)

This addresses a bug in which changes in mstatus could
propagate to RoCCs before their time. Existing RoCCs that use
the status port will need to be modified to match this change.

This addresses the first half of #40.

rocket/src/main/scala/rocket.scala

@@ -599,7 +599,7 @@ class Rocket(implicit p: Parameters) extends CoreModule()(p) {
 
   io.rocc.cmd.valid := wb_reg_valid && wb_ctrl.rocc && !replay_wb_common
   io.rocc.exception := wb_xcpt && csr.io.status.xs.orR
-  io.rocc.status := csr.io.status
+  io.rocc.cmd.bits.status := csr.io.status
   io.rocc.cmd.bits.inst := new RoCCInstruction().fromBits(wb_reg_inst)
   io.rocc.cmd.bits.rs1 := wb_reg_wdata
   io.rocc.cmd.bits.rs2 := wb_reg_rs2