* errno.cc (errmap): Add ERROR_TOO_MANY_LINKS -> EMLINK mapping.

* syscalls.cc (link): Only copy files if FS doesn't support hard links.

winsup/cygwin/errno.cc

@@ -120,6 +120,7 @@ static NO_COPY struct
   X (DEVICE_REQUIRES_CLEANING,	EIO),
   X (DEVICE_DOOR_OPEN,		EIO),
   X (IO_PENDING,		EAGAIN),
+  X (TOO_MANY_LINKS,		EMLINK),
   { 0, NULL, 0}
 };