Useless code in diskboot.S (not a bug)

[max]

Not a bug, just a trivial issue.

The code:
        /* save the sector number of the second sector in %ebp */
        movl    (%di), %ebp

does not appear to serve any purpose (ebp is never used unless I missed 
something). It caught my eye because I wanted to verify that this code was 
using 64-bit sector numbers everywhere.

Dan