net: only enable broadcast on sockets which support it
Only enable broadcast on SOCK_DGRAM and SOCK_RAW sockets, SOCK_STREAM
and others don't support it.
Don't enable SO_BROADCAST on UNIX domain sockets as they don't support it.
This caused failures on WSL which strictly checks setsockopt calls
unlike other OSes which often silently ignore bad options.
Also return error for setsockopt call for SO_BROADCAST on Windows
matching all other platforms but for IPv4 only as it's not supported
on IPv6 as per:
https://docs.microsoft.com/en-us/windows/win32/winsock/socket-options
Fixes #38954
Change-Id: I0503fd1ce96102b17121af548b66b3e9c2bb80d3
Reviewed-on: https://go-review.googlesource.com/c/go/+/232807
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>