endian_switch01: Fix build on older distros.

Fixes build failures:

...
In function `test_le_switch':
endian_switch01.c:84: undefined reference to `WIFSIGNALED'
endian_switch01.c:88: undefined reference to `WIFEXITED'
endian_switch01.c:85: undefined reference to `WTERMSIG'
endian_switch01.c:89: undefined reference to `WEXITSTATUS'
...
collect2: ld returned 1 exit status

Signed-off-by: Cyril Hrubis <[email protected]>

Author: metan-ucw

testcases/kernel/syscalls/switch/endian_switch01.c

@@ -27,6 +27,8 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <elf.h>
+#include <sys/types.h>
+#include <sys/wait.h>
 #include "tst_test.h"
 
 #if defined (__powerpc64__) || (__powerpc__)