syscalls.master: switch to CAPENABLED flags

Switch the main syscall table to use CAPENABLED flags rather than
capabilities.conf.  This avoid synchronization issues between
syscalls.master and capabilities.conf (e.g. when renaming a syscall
during development).

For now, move capabilities.conf to sys/compat/freebsd32 and use it
there.  Use of sys/compat/freebsd32/syscalls.master should be replaced
by makesyscalls.lua enhancements to allow the main one to be used.

This change results in no changes to generated files after running
`make sysent`.

Reviewed by:	kevans, emaste
MFC after:	1 week
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D31350

sys/compat/freebsd32/Makefile

@@ -3,5 +3,6 @@
 # $FreeBSD$
 
 GENERATED_PREFIX=	freebsd32_
+CAPABILITIES_CONF=	capabilities.conf
 
 .include "../../conf/sysent.mk"

sys/compat/freebsd32/syscalls.conf

@@ -10,4 +10,4 @@ switchname="freebsd32_sysent"
 namesname="freebsd32_syscallnames"
 systrace="freebsd32_systrace_args.c"
 abi_func_prefix="freebsd32_"
-capabilities_conf="../../kern/capabilities.conf"
+capabilities_conf="capabilities.conf"

sys/conf/sysent.mk

@@ -26,7 +26,6 @@ SRCS+=	${SYSENT_CONF}
 # even though it is not an explicit input to makesyscalls.lua.  For some
 # targets, like Linux system calls, this is unnecessary, but a spurious rebuild
 # is both rare and harmless.
-CAPABILITIES_CONF?= ${SYSDIR}/kern/capabilities.conf
 SRCS+=	${CAPABILITIES_CONF}
 
 MAKESYSCALLS_INTERP?=	${LUA}

sys/kern/Makefile

@@ -3,7 +3,6 @@
 #
 # Makefile for init_sysent
 
-SRCS+=		capabilities.conf
 SYSENT_CONF=
 GENERATED=	init_sysent.c			\
 		syscalls.c			\