[Skiboot] skiboot 5.0.1 tagged

[Stewart Smith]

Hi all,

We have skiboot-5.0.1 tagged.

It has the following fixes over skiboot-5.0:

- prd: Only alter host presentation bits of IPOLL mask
- init: Display message before loading kernel
- xscom: Remove recursive locking
- Add xscom_ok() and lpc_ok() to check XSCOM and LPC usability
    This fixes issues where the generation of error logs inside the LPC or
    XSCOM drivers could cause a re-entrancy (via the BT interface)
    causing deadlocks. Now, the error logs IPMI messages will be queued up
    and delivered later on the next poll handler.

Nothing major for this release, geared towards Habanero systems and
op-build 1.2.1

thanks,
stewart.