net: clear msg_get_inq in __get_compat_msghdr()

net: clear msg_get_inq in __get_compat_msghdr()

syzbot is still complaining uninit-value in tcp_recvmsg(), for
commit 1228b34c8d0ecf6d ("net: clear msg_get_inq in __sys_recvfrom() and
__copy_msghdr_from_user()") missed that __get_compat_msghdr() is called
instead of copy_msghdr_from_user() when MSG_CMSG_COMPAT is specified.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: 1228b34c8d0ecf6d ("net: clear msg_get_inq in __sys_recvfrom() and __copy_msghdr_from_user()")
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/d06d0f7f-696c-83b4-b2d5-70b5f2730a37@I-love.SAKURA.ne.jp
Signed-off-by: Jakub Kicinski <kuba@kernel.org>