[make] Fix missing outpath for custom flag files

tools/build_script_generator/make/resources/config.mk.in

@@ -9,6 +9,7 @@
 profile?=release
 BUILDPATH_PREFIX := {{ build_path }}/make-
 BUILDPATH := $(BUILDPATH_PREFIX)$(profile)
+OUTPATH := {{outpath}}
 MODM_PROJECT_NAME := {{ options[":build:project.name"] }}
 
 ELF_FILE := $(BUILDPATH)/$(MODM_PROJECT_NAME).{{program_extension}}
@@ -133,22 +134,22 @@ compile_asm = \
 $(BUILDPATH)/%.o : %.c
 	@$(call compile_c,$@,$<,)
 %% if outpath != "."
-$(BUILDPATH)/%.o : {{outpath}}/%.c
+$(BUILDPATH)/%.o : $(OUTPATH)/%.c
 	@$(call compile_c,$@,$<,)
 %% endif
 %% for suffix in ["cc", "cpp", "cxx", "c++"]
 $(BUILDPATH)/%.o : %.{{suffix}}
 	@$(call compile_cpp,$@,$<,)
 %% if outpath != "."
-$(BUILDPATH)/%.o : {{outpath}}/%.{{suffix}}
+$(BUILDPATH)/%.o : $(OUTPATH)/%.{{suffix}}
 	@$(call compile_cpp,$@,$<,)
 %% endif
 %% endfor
 %% for suffix in ["sx", "s", "S"]
 $(BUILDPATH)/%.o : %.{{suffix}}
 	@$(call compile_asm,$@,$<,)
 %% if outpath != "."
-$(BUILDPATH)/%.o : {{outpath}}/%.{{suffix}}
+$(BUILDPATH)/%.o : $(OUTPATH)/%.{{suffix}}
 	@$(call compile_asm,$@,$<,)
 %% endif
 %% endfor

tools/build_script_generator/make/resources/repo.mk.in

@@ -66,7 +66,7 @@ CPPDEFINES += \
 # Custom build rules for repo sources
 %% for file, flags in sources
 	%% if flags | length
-$(BUILDPATH)/{{ file | objectify }}: {{ file }}
+$(BUILDPATH)/{{ file | objectify }}: $(OUTPATH)/{{ file }}
 	%% set ext = {"sx":"asm","s":"asm","S":"asm"}.get(file.split(".")[-1],file.split(".")[-1])
 	@$(call compile_{{ ext }},$@,$<,{% for key, profiles in flags.items() if "" in profiles %} {{ profiles[""] | join(" ") }}{% endfor %} \
 		%% for key, profiles in flags.items()