ntsync: Introduce NTSYNC_IOC_SEM_POST.

ntsync: Introduce NTSYNC_IOC_SEM_POST.

This corresponds to the NT syscall NtReleaseSemaphore().

This increases the semaphore's internal counter by the given value, and returns
the previous value. If the counter would overflow the defined maximum, the
function instead fails and returns -EOVERFLOW.

Signed-off-by: Elizabeth Figura <zfigura@codeweavers.com>
Link: https://lore.kernel.org/r/20240329000621.148791-4-zfigura@codeweavers.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>