kern/kern_fork/exit.c: organize includes

Remove sys/cdefs.h.
Remove sys/param.h.
Order the sys/*.h includes alphabetically.

Reviewed by:	asomers, markj
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D54592

sys/kern/kern_exit.c

@@ -34,45 +34,43 @@
  * SUCH DAMAGE.
  */
 
-#include <sys/cdefs.h>
 #include "opt_ddb.h"
 #include "opt_ktrace.h"
 
-#include <sys/param.h>
 #include <sys/systm.h>
-#include <sys/sysproto.h>
+#include <sys/acct.h>		/* for acct_process() function prototype */
 #include <sys/capsicum.h>
 #include <sys/eventhandler.h>
+#include <sys/filedesc.h>
+#include <sys/jail.h>
 #include <sys/kernel.h>
 #include <sys/ktr.h>
-#include <sys/malloc.h>
 #include <sys/lock.h>
+#include <sys/malloc.h>
 #include <sys/mutex.h>
 #include <sys/proc.h>
 #include <sys/procdesc.h>
-#include <sys/jail.h>
-#include <sys/tty.h>
-#include <sys/wait.h>
-#include <sys/vmmeter.h>
-#include <sys/vnode.h>
+#include <sys/ptrace.h>
 #include <sys/racct.h>
 #include <sys/resourcevar.h>
 #include <sys/sbuf.h>
-#include <sys/signalvar.h>
 #include <sys/sched.h>
+#include <sys/sdt.h>
+#include <sys/sem.h>
+#include <sys/shm.h>
+#include <sys/signalvar.h>
 #include <sys/sx.h>
 #include <sys/syscallsubr.h>
 #include <sys/sysctl.h>
-#include <sys/syslog.h>
-#include <sys/ptrace.h>
-#include <sys/acct.h>		/* for acct_process() function prototype */
-#include <sys/filedesc.h>
-#include <sys/sdt.h>
-#include <sys/shm.h>
-#include <sys/sem.h>
 #include <sys/sysent.h>
+#include <sys/syslog.h>
+#include <sys/sysproto.h>
 #include <sys/timers.h>
+#include <sys/tty.h>
 #include <sys/umtxvar.h>
+#include <sys/vmmeter.h>
+#include <sys/vnode.h>
+#include <sys/wait.h>
 #ifdef KTRACE
 #include <sys/ktrace.h>
 #endif

sys/kern/kern_fork.c

@@ -34,20 +34,20 @@
  * SUCH DAMAGE.
  */
 
-#include <sys/cdefs.h>
 #include "opt_ktrace.h"
 #include "opt_kstack_pages.h"
 
-#include <sys/param.h>
 #include <sys/systm.h>
+#include <sys/acct.h>
 #include <sys/bitstring.h>
-#include <sys/sysproto.h>
 #include <sys/eventhandler.h>
 #include <sys/fcntl.h>
 #include <sys/filedesc.h>
 #include <sys/jail.h>
 #include <sys/kernel.h>
 #include <sys/kthread.h>
+#include <sys/ktr.h>
+#include <sys/ktrace.h>
 #include <sys/sysctl.h>
 #include <sys/lock.h>
 #include <sys/malloc.h>
@@ -60,17 +60,15 @@
 #include <sys/racct.h>
 #include <sys/resourcevar.h>
 #include <sys/sched.h>
+#include <sys/sdt.h>
+#include <sys/signalvar.h>
+#include <sys/sx.h>
 #include <sys/syscall.h>
+#include <sys/sysent.h>
+#include <sys/sysproto.h>
 #include <sys/vmmeter.h>
 #include <sys/vnode.h>
-#include <sys/acct.h>
-#include <sys/ktr.h>
-#include <sys/ktrace.h>
 #include <sys/unistd.h>
-#include <sys/sdt.h>
-#include <sys/sx.h>
-#include <sys/sysent.h>
-#include <sys/signalvar.h>
 
 #include <security/audit/audit.h>
 #include <security/mac/mac_framework.h>