Minor cleanups

libc/signal/sigblock.c

@@ -16,6 +16,7 @@ License along with the GNU C Library; see the file COPYING.LIB.  If
 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
 Cambridge, MA 02139, USA.  */
 
+#include <stdlib.h>
 #include <errno.h>
 #include <signal.h>
 

libc/signal/siggtmsk.c

@@ -16,6 +16,7 @@ License along with the GNU C Library; see the file COPYING.LIB.  If
 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
 Cambridge, MA 02139, USA.  */
 
+#include <stdlib.h>
 #include <errno.h>
 #include <signal.h>
 

libc/signal/sigstmsk.c

@@ -16,6 +16,7 @@ License along with the GNU C Library; see the file COPYING.LIB.  If
 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
 Cambridge, MA 02139, USA.  */
 
+#include <stdlib.h>
 #include <errno.h>
 #include <signal.h>