net: raw: revert unrelated change

Commit 5640f7685831 ("net: use a per task frag allocator")
accidentally contained an unrelated change to net/ipv4/raw.c,
later committed (without the pr_err() debugging bits) in
net tree as commit ab43ed8b749 (ipv4: raw: fix icmp_filter())

This patch reverts this glitch, noticed by Stephen Rothwell.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>