OpenSystemsDevelopment / usbboot

When not signing the configuration (no -k option), there's no
$TMP_CONFIG file and `test -f "$TMP_CONFIG"` is false. The whole line
becomes false and the script exists 1 for `set -e`.

This commit fixes that by moving the test to `if` condition.

Fixes: d1a9a5c659e8 ("beta: Add support for secure-boot - see Readme.md")
Signed-off-by: Wojtek Porczyk <woju@invisiblethingslab.com>

Include the new imager applications and fix the recursive File
operations to stop the installer pulling in the .git directory.

Add a few tidyups and a note about initramfs

Create a new rpiboot mode that uses a Linux initramfs to
implement mass-storage-gadget mode supporting EMMC and NVMe
block devices.

To use:
cd usbboot/mass-storage/gadget
../rpiboot -d .

Replace the example boot.img with a slightly more useful version
64-bit version that boots to a minimal busybox initrd with
USB enabled.

See https://github.com/raspberrypi/usbboot/issues/116

Fix help -c and -i default option

pieeprom-2022-02-08: Fix boot failure in locked secure-boot

The previous version would fail to boot if secure-boot mode was
locked via OTP settings.

recovery.bin prevent revoke_devkey from being set before the
customer key has been programmed.

Update bootloader to the latest stable release and use full SDRAM init in MSD / RAMDISK mode.

For test/debug purposes it's sometimes useful to erase the SPI
EEPROM using a chip-erase command. This has been available via
recovery.bin for a while but add it here for convenience.

The MSD (and secure-boot variant) bootloader has been updated to
fully initialise SDRAM in order to resolve problems when using
this method to run Linux ramdisks / initrd.
Therefore, MSD boot will not work on a system with a blank or
corrupted EEPROM. If so, an error message will be output to the
UART and the EEPROM should be programmed using the recovery
option.

e.g. previously, ../../filename would generate ../.sig

Previously, relative paths would confuse the file name generation regex.
With this change, only the final '.' character is matched as the
beginning of the file extension.

20220111~130126 release

rpiboot: Add build date and version

Capture the changelog version and git version (if available)

bootloader: Enable revoke_devkey in secure-boot recovery.bin

Enable the recovery config.txt options to revoke the ROM
development key which permentantely locks the device into
secure-boot mode.

WARNING: This also prevents the bootloader from being downgraded
to older releases which don't support secure-boot.

This is a very old test image and shouldn't be in this repo.
Since it's bit rotted remove it to avoid confusion.

The image should probably be published via a different repo.

Update the default EEPROM image to 2021-12-02