Haiku: Add platform support.

[kallisti5]

No description provided.

[kallisti5]

/Builds/LuaJIT> uname -a
Haiku catsmeow 1 hrev51055 Mar 31 2017 12:26:43 x86_64 x86_64 Haiku
/Builds/LuaJIT> make
==== Building LuaJIT 2.0.4 ====
make -C src
make[1]: Entering directory '/Builds/LuaJIT/src'
HOSTCC    host/minilua.o
HOSTLINK  host/minilua
DYNASM    host/buildvm_arch.h
HOSTCC    host/buildvm.o
HOSTCC    host/buildvm_asm.o
HOSTCC    host/buildvm_peobj.o
HOSTCC    host/buildvm_lib.o
HOSTCC    host/buildvm_fold.o
HOSTLINK  host/buildvm
BUILDVM   lj_vm.s
ASM       lj_vm.o
CC        lj_gc.o
BUILDVM   lj_ffdef.h
CC        lj_err.o
CC        lj_char.o
BUILDVM   lj_bcdef.h
CC        lj_bc.o
CC        lj_obj.o
CC        lj_str.o
CC        lj_tab.o
CC        lj_func.o
CC        lj_udata.o
CC        lj_meta.o
CC        lj_debug.o
CC        lj_state.o
CC        lj_dispatch.o
CC        lj_vmevent.o
CC        lj_vmmath.o
CC        lj_strscan.o
CC        lj_api.o
CC        lj_lex.o
CC        lj_parse.o
CC        lj_bcread.o
CC        lj_bcwrite.o
CC        lj_load.o
CC        lj_ir.o
CC        lj_opt_mem.o
BUILDVM   lj_folddef.h
CC        lj_opt_fold.o
CC        lj_opt_narrow.o
CC        lj_opt_dce.o
CC        lj_opt_loop.o
CC        lj_opt_split.o
CC        lj_opt_sink.o
CC        lj_mcode.o
CC        lj_snap.o
CC        lj_record.o
CC        lj_crecord.o
BUILDVM   lj_recdef.h
CC        lj_ffrecord.o
CC        lj_asm.o
CC        lj_trace.o
CC        lj_gdbjit.o
CC        lj_ctype.o
CC        lj_cdata.o
CC        lj_cconv.o
CC        lj_ccall.o
CC        lj_ccallback.o
CC        lj_carith.o
CC        lj_clib.o
CC        lj_cparse.o
CC        lj_lib.o
CC        lj_alloc.o
CC        lib_aux.o
BUILDVM   lj_libdef.h
CC        lib_base.o
CC        lib_math.o
CC        lib_bit.o
CC        lib_string.o
CC        lib_table.o
CC        lib_io.o
CC        lib_os.o
CC        lib_package.o
CC        lib_debug.o
CC        lib_jit.o
CC        lib_ffi.o
CC        lib_init.o
AR        libluajit.a
CC        luajit.o
BUILDVM   jit/vmdef.lua
DYNLINK   libluajit.so
LINK      luajit
OK        Successfully built LuaJIT
make[1]: Leaving directory '/Builds/LuaJIT/src'
==== Successfully built LuaJIT 2.0.4 ====
/Builds/LuaJIT> ./src/luajit 
LuaJIT 2.0.4 -- Copyright (C) 2005-2017 Mike Pall. http://luajit.org/
JIT: ON CMOV SSE2 SSE3 SSE4.1 fold cse dce fwd dse narrow loop abc sink fuse
> print("Hello World")Hello World
> 

[MikePall]

Added to v2.1. Thanks!

Please note this is not an officially supported target.