tools/init.d: wr_date: fix back TAI offset in kernel

Fix TAI offset into kernel was done withing get function but this has
been removed in commit #091f4c8d. As it is still needed by slave, we
force its use using -n option. This will only fix tai offset into kernel
without applying ToD to WR/FPGA time.

Conflicts:
	userspace/tools/wr_date.c