If we take an alignment exception which we cannot fix, the oops
currently prints:

Unable to handle kernel paging request for unknown fault

Lets print something more useful:

Unable to handle kernel paging request for unaligned access at address 0xc0000000f77bba8f
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>