<android-base/endian.h>: fix interoperability issue

<winsock2.h> has defined htonl(), ntohl(), htons() and ntohs() with
different return type that cannot be replaced by those macro definitions
in <android-base/endian.h>.

Includes <winsock2.h> first to prevent them from being replaced.
Then defines the macro later so we don't need to call into DLL
when using those functions.

Bug: 139639521
Test: m libbase_test && wine out/host/windows-x86/nativetest64/libbase_test/libbase_test64.exe
Test: m checkbuild
Change-Id: I672f23a31c6800df10e04d36695d446bca4c91e9