Fix DragonFly build (php#13085)

On DragonFly by default the BSD make is used with the CSH shell and the
first prerequisite variable `$<` in Makefile doesn't work there. So, we
can simplify this by simply repeating the filename here.

Author: petk

ext/opcache/jit/Makefile.frag

@@ -8,7 +8,7 @@ $(builddir)/jit/ir/ir_emit.lo: \
 	$(srcdir)/jit/ir/ir_emit.c $(builddir)/jit/ir/ir_emit_$(DASM_ARCH).h
 
 $(builddir)/jit/ir/gen_ir_fold_hash: $(srcdir)/jit/ir/gen_ir_fold_hash.c $(srcdir)/jit/ir/ir_strtab.c
-	$(BUILD_CC) -D${IR_TARGET} -DIR_PHP -DIR_PHP_MM=0 -o $@ $<
+	$(BUILD_CC) -D${IR_TARGET} -DIR_PHP -DIR_PHP_MM=0 -o $@ $(srcdir)/jit/ir/gen_ir_fold_hash.c
 
 $(builddir)/jit/ir/ir_fold_hash.h: $(builddir)/jit/ir/gen_ir_fold_hash $(srcdir)/jit/ir/ir_fold.h $(srcdir)/jit/ir/ir.h
 	$(builddir)/jit/ir/gen_ir_fold_hash < $(srcdir)/jit/ir/ir_fold.h > $(builddir)/jit/ir/ir_fold_hash.h