Revert to exposing sys/select.h from sys/time.h on Cygwin

* libc/include/sys/time.h: Include sys/select.h on Cygwin.  Explain why.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

newlib/ChangeLog

@@ -1,3 +1,7 @@
+2015-05-02  Corinna Vinschen  <vinschen@redhat.com>
+
+	* libc/include/sys/time.h: Include sys/select.h on Cygwin.  Explain why.
+
 2015-04-29  Corinna Vinschen  <vinschen@redhat.com>
 
 	* libc/include/sys/config.h: Move evaluation of _UINTPTR_EQ_ULONG and

newlib/libc/include/sys/time.h

@@ -42,6 +42,12 @@
 #include <sys/types.h>
 #include <sys/timespec.h>
 
+/* Cygwin exposes sys/select.h to users of sys/time.h for a couple of years
+   so we have to maintain that.  Note that this is in accordance with POSIX. */
+#ifdef __CYGWIN__
+#include <sys/select.h>
+#endif /* __CYGWIN__ */
+
 struct timezone {
 	int	tz_minuteswest;	/* minutes west of Greenwich */
 	int	tz_dsttime;	/* type of dst correction */