Make the cloudabi32 kernel module available on ARMv6.

Now that all of the necessary bits for ARMv6 support for CloudABI have
been checked in, let's hook the kernel module up to the build and
document its existence.

share/man/man4/cloudabi.4

@@ -22,7 +22,7 @@
 .\" SUCH DAMAGE.
 .\"
 .\" $FreeBSD$
-.Dd August 24, 2016
+.Dd September 22, 2016
 .Dt CLOUDABI 4
 .Os
 .Sh NAME
@@ -84,7 +84,7 @@ module can be loaded on any architecture supported by
 .Fx ,
 the
 .Nm cloudabi32
-module is only available on i386 and amd64.
+module is only available on amd64, armv6 and i386.
 The same holds for the
 .Nm cloudabi64
 module,

sys/modules/Makefile

@@ -768,7 +768,8 @@ _epic=		epic
 _igb=		igb
 .endif
 
-.if ${MACHINE_CPUARCH} == "amd64" || ${MACHINE_CPUARCH} == "i386"
+.if (${MACHINE_CPUARCH} == "amd64" || ${MACHINE_ARCH} == "armv6" || \
+     ${MACHINE_CPUARCH} == "i386")
 _cloudabi32=	cloudabi32
 .endif
 .if ${MACHINE_CPUARCH} == "aarch64" || ${MACHINE_CPUARCH} == "amd64"

sys/modules/cloudabi32/Makefile

@@ -14,14 +14,18 @@ SRCS=	cloudabi32_fd.c cloudabi32_module.c cloudabi32_poll.c \
 OBJS=	cloudabi32_vdso_blob.o
 CLEANFILES=cloudabi32_vdso.o
 
-.if ${MACHINE_CPUARCH} == "i386"
-VDSO_SRCS=${SYSDIR}/contrib/cloudabi/cloudabi_vdso_i686.S
-OUTPUT_TARGET=elf32-i386-freebsd
-BINARY_ARCHITECTURE=aarch32
-.elif ${MACHINE_CPUARCH} == "amd64"
+.if ${MACHINE_CPUARCH} == "amd64"
 VDSO_SRCS=${SYSDIR}/contrib/cloudabi/cloudabi_vdso_i686_on_64bit.S
 OUTPUT_TARGET=elf64-x86-64-freebsd
 BINARY_ARCHITECTURE=i386
+.elif ${MACHINE_ARCH} == "armv6"
+VDSO_SRCS=${SYSDIR}/contrib/cloudabi/cloudabi_vdso_armv6.S
+OUTPUT_TARGET=elf32-littlearm
+BINARY_ARCHITECTURE=arm
+.elif ${MACHINE_CPUARCH} == "i386"
+VDSO_SRCS=${SYSDIR}/contrib/cloudabi/cloudabi_vdso_i686.S
+OUTPUT_TARGET=elf32-i386-freebsd
+BINARY_ARCHITECTURE=i386
 .endif
 
 cloudabi32_vdso.o: ${VDSO_SRCS}