alloc failures already get standardized OOM
messages and a dump_stack.

Convert kzalloc's with multiplies to kcalloc.
Convert kmalloc's with multiplies to kmalloc_array.
Remove now unused variables.
Remove unnecessary memset after kzalloc->kcalloc.
Whitespace cleanups for these changes.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>