pieeprom-2021-04-29: Update default release to this image

Author: timg236

firmware/critical/pieeprom-2021-04-29.bin

@@ -3,6 +3,9 @@
 USB MSD boot also requires the firmware from Raspberry Pi OS 2020-08-20 or newer.
 https://www.raspberrypi.org/documentation/hardware/raspberrypi/bcm2711_bootloader_config.md
 
+## 2021-04-30 - Update default version to 2021-04-29
+   * The manufacturing release has been updated to pieeprom-2021-04-29 so update the default release to match this.
+
 ## 2021-04-29 - Pi400 - Reduce MII clock freq when probing ethernet PHY - STABLE
    * Pi400 - Reduce MII clock freq when probing ethernet PHY - STABLE