Makefile.include: Use LDLIBS & LIBDEPS

Makefile.include

@@ -82,13 +82,18 @@ LDFLAGS  += --static \
             -Wl,--end-group \
             -L$(TOP_DIR) \
             -L$(TOOLCHAIN_DIR)/lib \
-            -L$(TOOLCHAIN_DIR)/lib/stm32/f2 \
             -T$(LDSCRIPT) \
             -nostartfiles \
             -Wl,--gc-sections \
             $(CPUFLAGS) \
             $(FPUFLAGS)
 
+LDLIBS   += -ltrezor
+LIBDEPS  += $(TOP_DIR)/libtrezor.a
+
+LDLIBS   += -lopencm3_stm32f2
+LIBDEPS  += $(TOOLCHAIN_DIR)/lib/libopencm3_stm32f2.a
+
 all: $(NAME).bin
 
 flash: $(NAME).bin
@@ -127,8 +132,8 @@ $(NAME).srec: $(NAME).elf
 $(NAME).list: $(NAME).elf
 	$(OBJDUMP) -S $(NAME).elf > $(NAME).list
 
-$(NAME).elf: $(OBJS) $(LDSCRIPT) $(TOOLCHAIN_DIR)/lib/libopencm3_stm32f2.a $(TOP_DIR)/libtrezor.a
-	$(LD) -o $(NAME).elf $(OBJS) -ltrezor -lopencm3_stm32f2 $(LDFLAGS)
+$(NAME).elf: $(OBJS) $(LDSCRIPT) $(LIBDEPS)
+	$(LD) -o $(NAME).elf $(OBJS) $(LDLIBS) $(LDFLAGS)
 
 %.o: %.s Makefile
 	$(AS) $(CPUFLAGS) -o $@ $<