Include <fcntl.h> from a header using fcntl().

No real changes, just make the header self-containing instead of relying on
the file including it to include <fcntl.h> itself.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74344 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/unix/utilsunx.cpp

@@ -116,7 +116,6 @@
 #include <errno.h>
 #include <netdb.h>
 #include <signal.h>
-#include <fcntl.h>          // for O_WRONLY and friends
 #include <time.h>           // nanosleep() and/or usleep()
 #include <ctype.h>          // isspace()
 #include <sys/time.h>       // needed for FD_SETSIZE