Some hardware is very well intentioned. However this intention
can result in the UEFI NVRAM table being full which prevents us
from adding new records to the table. We can't be sure what to
delete, so in this case some operators just need the ability to
tell ironic "it is okay if this fails, it will still work."
The added ``ignore_bootloader_failure`` option adds
this capability which can be set per-node either in the agent
configuation via the ramdisk image, or in the pxe_append_params
configuration parameter for the node itself with a
``ipa-ignore-bootloader-failure`` option in order to prevent
the failure from being raised.
Change-Id: If3c83fb2ea2025fce092d495a64f32077c70d2d6
Story: 2008386
Task: 41309
7a83773fbc