hwclock: update set_system_clock debugging

hwclock: update set_system_clock debugging

Update debug messages for a combined --systz and --hctosys in
the set_system_clock function.

New debug messages:

hwclock --test -D --systz --localtime
Calling settimeofday(NULL, 240) to warp System time.
Test mode: clock was not changed

hwclock --test -D --systz --utc
Calling settimeofday(NULL, 0) to lock the warp function.
Calling settimeofday(NULL, 240) to set the kernel timezone.
Test mode: clock was not changed

hwclock --test -D --hctosys --utc
Calling settimeofday(1502239269.733639, 240)
Test mode: clock was not changed

hwclock --test -D --hctosys --localtime
Calling settimeofday(NULL, 240) to set persistent_clock_is_local.
Calling settimeofday(1502253708.200200, 240)
Test mode: clock was not changed

Signed-off-by: J William Piggott <elseifthen@gmx.com>