Add Makefiles for CloudABI kernel modules.

Place all of the machine/pointer size independent code in a kernel
module called 'cloudabi'. All of the 64-bit specific code goes in a
separate module called 'cloudabi64'. The latter is only enabled on
amd64, as it is the only architecture supported.

sys/modules/Makefile

@@ -72,6 +72,8 @@ SUBDIR=	\
 	${_ce} \
 	${_cfi} \
 	${_ciss} \
+	cloudabi \
+	${_cloudabi64} \
 	${_cm} \
 	${_cmx} \
 	${_coff} \
@@ -616,6 +618,7 @@ _x86bios=	x86bios
 .endif
 
 .if ${MACHINE_CPUARCH} == "amd64"
+_cloudabi64=	cloudabi64
 _ixl=		ixl
 _ixlv=		ixlv
 _linux64=	linux64

sys/modules/cloudabi/Makefile

@@ -0,0 +1,10 @@
+# $FreeBSD$
+
+.PATH: ${.CURDIR}/../../compat/cloudabi
+
+KMOD=	cloudabi
+SRCS=	cloudabi_clock.c cloudabi_errno.c cloudabi_fd.c cloudabi_file.c \
+	cloudabi_futex.c cloudabi_mem.c cloudabi_proc.c cloudabi_random.c \
+	cloudabi_sock.c cloudabi_thread.c vnode_if.h
+
+.include <bsd.kmod.mk>

sys/modules/cloudabi64/Makefile

@@ -0,0 +1,11 @@
+# $FreeBSD$
+
+.PATH: ${.CURDIR}/../../compat/cloudabi64
+.PATH: ${.CURDIR}/../../${MACHINE_CPUARCH}/cloudabi64
+
+KMOD=	cloudabi64
+SRCS=	cloudabi64_fd.c cloudabi64_poll.c cloudabi64_sock.c \
+	cloudabi64_syscalls.c cloudabi64_sysent.c cloudabi64_sysvec.c \
+	cloudabi64_thread.c
+
+.include <bsd.kmod.mk>