tg3: Fix message 80 char violations

Commit 05dbe005

, "Use (pr|netdev)_<level>
macro helpers" extended some of the message lines longer than 80 chars.
This patch reels the line lengths back in.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>