restorer.c: rm unneded struct init

This 'struct timespec' initialization is non needed as we call
clock_gettime() right away which is supposed to fill it in.

The real reason of removing this init is when compiled by clang
with -O0 etc (i.e. compiler flags set when GCOV=1 env var is present),
clang inserts a call to memset to initialize the structure. This,
of course, leads to "compel piegen" complaining:

	Unexpected undefined symbol: `memset'. External symbol in PIE?

One way of solving it would be to provide a memset() which will call
builtin_memset(), or a simple C implemenation. But as this is the only
place that triggers such a call to memset(), and this initialization
is not really needed, it's easier just to remove it.

Now, there might be more cases like this in the future, but for now
we are good.

Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>