Remove now-unnecessary poll, fcntl includes from net(base).cpp

As far as I can tell, the code calling for these includes was removed in:
6e68ccbefe #24356
82d360b5a8 #21387

src/net.cpp

@@ -37,18 +37,12 @@
 
 #ifdef WIN32
 #include <string.h>
-#else
-#include <fcntl.h>
 #endif
 
 #if HAVE_DECL_GETIFADDRS && HAVE_DECL_FREEIFADDRS
 #include <ifaddrs.h>
 #endif
 
-#ifdef USE_POLL
-#include <poll.h>
-#endif
-
 #include <algorithm>
 #include <array>
 #include <cstdint>

src/netbase.cpp

@@ -21,14 +21,6 @@
 #include <limits>
 #include <memory>
 
-#ifndef WIN32
-#include <fcntl.h>
-#endif
-
-#ifdef USE_POLL
-#include <poll.h>
-#endif
-
 // Settings
 static GlobalMutex g_proxyinfo_mutex;
 static Proxy proxyInfo[NET_MAX] GUARDED_BY(g_proxyinfo_mutex);