linux-user: Add support for SIOCSPGRP ioctl for all targets

linux-user: Add support for SIOCSPGRP ioctl for all targets

Add support for setting the process (or process group) to receive SIGIO
or SIGURG signals when I/O becomes possible or urgent data is available,
using SIOCSPGRP ioctl.

The ioctl numeric values for SIOCSPGRP are platform-dependent and are
determined by following files in Linux kernel source tree:

arch/ia64/include/uapi/asm/sockios.h:#define SIOCSPGRP    0x8902
arch/mips/include/uapi/asm/sockios.h:#define SIOCSPGRP    _IOW('s', 8, pid_t)
arch/parisc/include/uapi/asm/sockios.h:#define SIOCSPGRP  0x8902
arch/sh/include/uapi/asm/sockios.h:#define SIOCSPGRP      _IOW('s', 8, pid_t)
arch/xtensa/include/uapi/asm/sockios.h:#define SIOCSPGRP  _IOW('s', 8, pid_t)
arch/alpha/include/uapi/asm/sockios.h:#define SIOCSPGRP   _IOW('s', 8, pid_t)
arch/sparc/include/uapi/asm/sockios.h:#define SIOCSPGRP   0x8902
include/uapi/asm-generic/sockios.h:#define SIOCSPGRP      0x8902

Hence the different definition for alpha, mips, sh4, and xtensa.

Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <1558282527-22183-3-git-send-email-aleksandar.markovic@rt-rk.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>