[U-Boot] Limit on length of U_BOOT_VERSION_STRING for mpc85xx

[Steve Heckman]

I was wondering if there was a limit on the size of the version string
U_BOOT_VERSION_STRING
in start.S.

There are 256 bytes available for the Magic Number, version_string
(U_BOOT_VERSION_STRING)
and _start_cont code.

We want to put clearcase build view information in as part of the
version_string, but were wondering if there were length restrictions.

Thanks,
Steve Heckman
Google/Motorola