net: ethernet: ti: cpts: Fix timestamp print

On 64-bit hosts we will get the following warning:

drivers/net/ethernet/ti/cpts.c: In function 'cpts_overflow_check':
drivers/net/ethernet/ti/cpts.c:297:11: warning: format '%lld' expects
argument of type 'long long int', but argument 3 has type
'__kernel_time_t {aka long int}' [-Wformat=]
  pr_debug("cpts overflow check at %lld.%09lu\n", ts.tv_sec,
ts.tv_nsec);

Fix this by using an appropriate casting that works on all bit sizes.

Fixes: a5c79c26 ("ptp: cpts: convert to the 64 bit get/set time methods.")
Fixes: 87c0e764

 ("cpts: introduce time stamping code and a PTP hardware clock.")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>