[JIT] Compile minilua with only the needed flags

Issue #999 seems to be avoidable mostly by restricting minilua to
compile with just the libraries that it needs, rather than all that
MoarVM brings in. Or thats' my theory at least.
Removes the always-recompile behaviour, which was annoying me.

build/Makefile.in

@@ -485,18 +485,16 @@ TOM_OBJECTS = @tomobjects@
 THIRDPARTY = @thirdpartylibs@
 
 MINILUA = 3rdparty/dynasm/minilua@exe@
+MINILUA_LDFLAGS = -lm
 DYNASM  = $(MINILUA) 3rdparty/dynasm/dynasm.lua
 DYNASM_SCRIPTS = 3rdparty/dynasm/dynasm.lua 3rdparty/dynasm/dasm_x86.lua
 DYNASM_HEADERS = 3rdparty/dynasm/dasm_proto.h 3rdparty/dynasm/dasm_x86.h
 
 .SUFFIXES: .c @obj@ .i @asm@ .dasc .expr .tile .h
-.PHONY: clean realclean install ALWAYS_REBUILD lib all help test reconfig clangcheck gcccheck libuv tracing cgoto switch no-tracing no-cgoto distclean release sandwich
+.PHONY: clean realclean install lib all help test reconfig clangcheck gcccheck libuv tracing cgoto switch no-tracing no-cgoto distclean release sandwich
 
 all: moar@exe@ pkgconfig/moar.pc
 
-# Empty target, just in case our make doesn't support the .PHONY property
-ALWAYS_REBUILD:
-
 install: all
 	$(MKPATH) "$(DESTDIR)$(BINDIR)"
 	$(CP) moar@exe@ "$(DESTDIR)$(BINDIR)"
@@ -616,9 +614,9 @@ src/strings/unicode.c: src/strings/unicode_db.c src/strings/unicode_uca.c src/st
 	$(MSG) generating $@
 	$(CMD) $(CAT) src/strings/unicode_db.c src/strings/unicode_uca.c src/strings/unicode_ops.c > $@ $(NOERR)
 
-# Always rebuild minilua to workaround issue #999
-$(MINILUA): ALWAYS_REBUILD 3rdparty/dynasm/minilua.c
-	$(CC) $(CFLAGS) $(LDFLAGS) 3rdparty/dynasm/minilua.c -o $@ $(LDLIBS)
+# Minilua requires only -lm, no libraries
+$(MINILUA): 3rdparty/dynasm/minilua.c
+	$(CC) $(MINILUA_LDFLAGS) 3rdparty/dynasm/minilua.c -o $@
 
 .dasc.c:
 	$(MSG) preprocessing $<