tools/build/make_libc_exterr_cat_filenames.sh: stabilize output
Sort the list of the source files to ensure that all runs get the same
output.
kern/kern_exit.c: some style
kern/kern_fork/exit.c: organize includes
Remove sys/cdefs.h.
Remove sys/param.h.
Order the sys/*.h includes alphabetically.
kern/kern_fork.c: define the exterror category for fork
Convert EINVALs in kern_fork.c into EXTERRORs.
sys: add AUE_PDRFORK
contrib/openbsm: add AUE_PDRFORK
sys: add pdrfork(2)
lib/libsys, lib/libc: export pdrfork(2)
kern/kern_exit.c: define the exterror category for exit/wait
Convert EINVALs in kern_exit.c into EXTERRORs.
kern/kern_exit.c: extract some helpers from proc_to_reap()
kern/kern_exit.c: extract wait6_check_alive() helper
Add pdwait(2)
lib/libsys, lib/libc: export pdwait
Regen for the fork and exit/wait exterror category addition
Regen syscall tables after pdfork(2) and pdwait(2) additions