tools: bpftool: fix dependency file path

Auto-generated dependency files are in the OUTPUT directory,
we need to include them from there.  This fixes object files
not being rebuilt after header changes.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/bpf/bpftool/Makefile

@@ -70,7 +70,7 @@ ifeq ($(feature-disassembler-four-args), 1)
 CFLAGS += -DDISASM_FOUR_ARGS_SIGNATURE
 endif
 
-include $(wildcard *.d)
+include $(wildcard $(OUTPUT)*.d)
 
 all: $(OUTPUT)bpftool