[mlnx-onie-fw-update] Fix reboot script usage

[stepanblyschak]

/usr/local/bin/reboot could return execution back to the invoking script in case of using graceful reboot. So, exit the script with reboot return code instead of proceeding with execution.

Why I did it

Fix BIOS fw update procedure.

Work item tracking

• Microsoft ADO (number only):

How I did it

Return exit code from reboot script in mlnx-onie-fw-update.sh

How to verify it

Tested with successful reboot:

root@r-leopard-58:/home/admin# sudo fwutil install chassis component BIOS fw <url>
Downloading firmware:
[##########################################################################################################################################################################################]  100%
Warning: Immediate cold reboot is required to complete BIOS firmware update.
New firmware will be installed, continue? [y/N]: y
Installing firmware:
    /tmp/0ACLH004.rom
INFO: Staging BIOS firmware update with ONIE updater
Staging firmware update: /tmp/99-0ACLH004.rom
** Pending firmware update information:
Name            | Version / Type | Attempts |Size (Bytes)  | Date
================+================+==========+==============+====================
99-0ACLH004.rom | bios_update    |        0 |      8388608 | 2024-04-24 14:12:19
================+================+==========+==============+====================

For more detailed information run: onie-fwpkg show-pending <update_name>
INFO: Rebooting in 5 sec...
/var/log: 3.6 GiB (3896754176 bytes) trimmed on /dev/loop1
/host: 23.2 GiB (24865517568 bytes) trimmed on /dev/sda3

INFO: firmware is up to date

Watchdog armed for 180 seconds
Wed 24 Apr 2024 02:12:34 PM UTC Issuing OS-level reboot ...
root@r-leopard-58:/home/admin# Connection to r-leopard-58 closed by remote host.

Failed reboot case (reboot script returned non zero exit code):

root@r-leopard-58:/home/admin# sudo fwutil install chassis component BIOS fw <url>
Downloading firmware:
[##########################################################################################################################################################################################]  100%
Warning: Immediate cold reboot is required to complete BIOS firmware update.
New firmware will be installed, continue? [y/N]: y
Installing firmware:
    /tmp/0ACLH004.rom
INFO: Staging BIOS firmware update with ONIE updater
Removing firmware update results: 99-0ACLH004.rom
Staging firmware update: /tmp/99-0ACLH004.rom
** Pending firmware update information:
Name            | Version / Type | Attempts |Size (Bytes)  | Date
================+================+==========+==============+====================
99-0ACLH004.rom | bios_update    |        0 |      8388608 | 2024-04-24 14:19:19
================+================+==========+==============+====================

For more detailed information run: onie-fwpkg show-pending <update_name>
INFO: Rebooting in 5 sec...
/var/log: 3.6 GiB (3859709952 bytes) trimmed on /dev/loop1
/host: 23.1 GiB (24844869632 bytes) trimmed on /dev/sda3

INFO: firmware is up to date

Removing pending firmware update: 99-0ACLH004.rom
ERROR: Failed to update BIOS firmware: Failed to trigger firmware update: Command '['/usr/bin/mlnx-onie-fw-update.sh', 'update']' returned non-zero exit status 1.
Error: Firmware install failed.

Which release branch to backport (provide reason below if selected)

• 201811
• 201911
• 202006
• 202012
• 202106
• 202111
• 202205
• 202211
• 202305
• 202311

Tested branch (Please provide the tested image version)

Description for the changelog

Link to config_db schema for YANG module changes

A picture of a cute animal (not mandatory but encouraged)