Revert "icmp: Add counters for rate limits"

This reverts commit 3ff50bc6 which is
commit d0941130 upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: I45a0407c330d682047d4fba1fbabfb245cd0fe5f
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>