Add a few missing includes

elf.h needs __BYTE_ORDER, and s_scalbn.c needs {LONG,INT}_MAX.
shm.c complains about no prototypes for shm_{open,unlink} without its header.

Signed-off-by: Ron Lee <ron@debian.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

include/elf.h

@@ -28,6 +28,7 @@ extern "C" {
 /* Standard ELF types.  */
 
 #include <stdint.h>
+#include <endian.h>
 
 /* Type for a 16-bit quantity.  */
 typedef uint16_t Elf32_Half;

libm/s_scalbn.c

@@ -18,6 +18,7 @@
 
 #include "math.h"
 #include "math_private.h"
+#include <limits.h>
 
 static const double
 two54  = 1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */

librt/shm.c

@@ -6,6 +6,7 @@
 #include <features.h>
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <sys/mman.h>
 #include <fcntl.h>
 #include <unistd.h>
 #include <stdlib.h>