Drop qemu_foo() socket API wrapper

Drop qemu_foo() socket API wrapper

The socket API wrappers were initially introduced in commit
00aa0040 ("Wrap recv to avoid warnings"), but made redundant with
commit a2d96af4 ("osdep: add wrappers for socket functions") which fixes
the win32 declarations and thus removed the earlier warnings.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>