linux-user: Add support for selected alsa timer instructions using ioctls

linux-user: Add support for selected alsa timer instructions using ioctls

This patch implements functionalities of following ioctls:

SNDRV_TIMER_IOCTL_START - Start selected alsa timer

    Starts the timer device that is selected. The third ioctl's argument is
    ignored. Before calling this ioctl, the ioctl "SNDRV_TIMER_IOCTL_SELECT"
    should be called first to select the timer that is to be started. If no
    timer is selected, the error EBADFD ("File descriptor in bad shape")
    is returned.

SNDRV_TIMER_IOCTL_STOP - Stop selected alsa timer

    Stops the timer device that is selected. The third ioctl's argument is
    ignored. Before calling this ioctl, the ioctl "SNDRV_TIMER_IOCTL_SELECT"
    should be called first to select the timer that is to be stopped. If no
    timer is selected, the error EBADFD ("File descriptor in bad shape")
    is returned.

SNDRV_TIMER_IOCTL_CONTINUE - Continue selected alsa timer

    Continues the timer device that is selected. The third ioctl's argument is
    ignored. Before calling this ioctl, the ioctl "SNDRV_TIMER_IOCTL_SELECT"
    should be called first to select the timer that is to be continued. If no
    timer is selected, the error EBADFD ("File descriptor in bad shape")
    is returned.

SNDRV_TIMER_IOCTL_PAUSE - Pause selected alsa timer

    Pauses the timer device that is selected. The third ioctl's argument is
    ignored. Before calling this ioctl, the ioctl "SNDRV_TIMER_IOCTL_SELECT"
    should be called first to select the timer that is to be paused. If no
    timer is selected, the error EBADFD ("File descriptor in bad shape")
    is returned.

Implementation notes:

    Since all of the implemented ioctls have NULL as their third argument,
    their implementation was straightforward.

Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Filip Bozuta <Filip.Bozuta@rt-rk.com>
Message-Id: <1579117007-7565-13-git-send-email-Filip.Bozuta@rt-rk.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>