net/IPv[46]Address: make the initializers even more portable

Similar to 5a5229b49943c7032d83ae665552b4dc3e334820: use more C++14
constexpr.

src/net/IPv4Address.hxx

@@ -51,7 +51,12 @@ class IPv4Address {
 #ifdef _WIN32
 	static constexpr struct in_addr ConstructInAddr(uint8_t a, uint8_t b,
 							uint8_t c, uint8_t d) noexcept {
-		return {{{ a, b, c, d }}};
+		struct in_addr result{};
+		result.s_net = a;
+		result.s_host = b;
+		result.s_lh = c;
+		result.s_impno = d;
+		return result;
 	}
 #else
 
@@ -66,7 +71,7 @@ class IPv4Address {
 
 	static constexpr struct in_addr ConstructInAddr(uint8_t a, uint8_t b,
 							uint8_t c, uint8_t d) noexcept {
-		return { ConstructInAddrT(a, b, c, d) };
+		return ConstructInAddrBE(ConstructInAddrT(a, b, c, d));
 	}
 #endif
 

src/net/IPv6Address.hxx

@@ -53,22 +53,24 @@ class IPv6Address {
 						   uint16_t c, uint16_t d,
 						   uint16_t e, uint16_t f,
 						   uint16_t g, uint16_t h) noexcept {
-		return {{
-			#ifndef __HAIKU__
-				{
-			#endif
-			uint8_t(a >> 8), uint8_t(a),
-			uint8_t(b >> 8), uint8_t(b),
-			uint8_t(c >> 8), uint8_t(c),
-			uint8_t(d >> 8), uint8_t(d),
-			uint8_t(e >> 8), uint8_t(e),
-			uint8_t(f >> 8), uint8_t(f),
-			uint8_t(g >> 8), uint8_t(g),
-			uint8_t(h >> 8), uint8_t(h),
-			#ifndef __HAIKU__
-				}
-			#endif
-		}};
+		struct in6_addr result{};
+		result.s6_addr[0] = a >> 8;
+		result.s6_addr[1] = a;
+		result.s6_addr[2] = b >> 8;
+		result.s6_addr[3] = b;
+		result.s6_addr[4] = c >> 8;
+		result.s6_addr[5] = c;
+		result.s6_addr[6] = d >> 8;
+		result.s6_addr[7] = d;
+		result.s6_addr[8] = e >> 8;
+		result.s6_addr[9] = e;
+		result.s6_addr[10] = f >> 8;
+		result.s6_addr[11] = f;
+		result.s6_addr[12] = g >> 8;
+		result.s6_addr[13] = g;
+		result.s6_addr[14] = h >> 8;
+		result.s6_addr[15] = h;
+		return result;
 	}
 
 	static constexpr struct sockaddr_in6 Construct(struct in6_addr address,