meta-raspberrypi: subtree update:a6f1233d52..0d398a3b71

Christopher Clark (1):
      linux-raspberrypi: bump to 5.4.50 since upstream was force-pushed

Leon Anavi (2):
      rpi-u-boot-scr: Create uboot.env via boot.cmd.in
      libubootenv_%.bbappend: Add fw_env.config

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: I8994cad6a13e2ae6f74c7a0a34061a9c4700a124