Fix race condition when changing SR when audio got misaligned

lib_xua/src/core/audiohub/xua_audiohub.xc

@@ -805,6 +805,7 @@ void XUA_AudioHub(chanend ?c_aud, clock ?clk_audio_mclk, clock ?clk_audio_bclk,
             /* Notify clockgen of new mCLk */
             c_mclk_change <: mClk;
             c_mclk_change <: curFreq;
+            c_mclk_change :> int _; /* Acknowledge when clocks all setup */
 #endif
         }
 

lib_xua/src/core/clocking/clockgen.xc

@@ -556,6 +556,7 @@ void clockGen ( streaming chanend ?c_spdif_rx,
                     InitSWPLL(sw_pll, selected_mclk_rate);
                     reset_sw_pll_pfd = 1;
                     printstr("swpll int'd\n");
+                    c_mclk_change <: 0; /* Acknowledge to hold off starting audio until done */
 #endif
                     break;
 #endif