[PATCH] ppc64: fix reloc_offset comment

The code in reloc_offset is actually subtracting the address in the link
register from the address calculated by the linker.  Perhaps the
extended mnemonic `sub' replaced an original `subf' and the comment just
did not get updated.

        bl      1f
1:      mflr    r3
        LOADADDR(r4,1b)
        sub     r3,r4,r3

Signed-off-by: Amos Waterland <apw@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>