qemu-sockets: Fix compiler warning (regression for MinGW)
setsockopt needs a type cast for MinGW. That type cast is missing in
a recent commit which results in a compiler warning.
Like for other socket related functions which have the same problem,
we add a 'qemu_setsockopt' macro which provides that type cast where
needed and use the new macro to avoid the warning.
A 'qemu_getsockopt' is also added and can be used for future
modifications.
Signed-off-by: Stefan Weil <sw@weilnetz.de> Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>