Added 6.21 to changelog (BCD_DEVICE bump)

CHANGELOG.rst

@@ -1,12 +1,16 @@
 sc_usb_audio Change Log
 =======================
 
+6.21.0
+------
+    - RESOLVED:   PDM microphone clock divide now based MCLK defines (previously hard-coded)
+
 6.20.0
 ------
     - RESOLVED:   Intra-frame sample delays of 1/2 samples on input streaming in TDM mode 
     - RESOLVED:   Build issue with NUM_USB_CHAN_OUT set to 0 and MIXER enabled
     - RESOLVED:   SPDIF_TX_INDEX not defined build warning only emitted when SPDIF_TX defined
-    - RESOLVED:  Failure to enter DFU mode when configured without input volume control
+    - RESOLVED:   Failure to enter DFU mode when configured without input volume control
 
 6.19.0
 ------

module_usb_audio/devicedefines.h

@@ -482,7 +482,7 @@
  * @brief Device firmware version number in Binary Coded Decimal format: 0xJJMN where JJ: major, M: minor, N: sub-minor version number.
  */
 #ifndef BCD_DEVICE_N
-#define BCD_DEVICE_N             0
+#define BCD_DEVICE_N             1
 #endif
 
 /**