make `make clean` work again

the irq2nvic_h generates files in a way make doesn't understand, so it
now also provides an option to clean up again

Makefile

@@ -45,6 +45,12 @@ generatedheaders:
 		./scripts/irq2nvic_h $$yamlfile ; \
 	done
 
+cleanheaders:
+	@printf "  CLEANING HEADERS\n"
+	$(Q)for yamlfile in `find -name 'irq.yaml'`; do \
+		./scripts/irq2nvic_h --remove $$yamlfile ; \
+	done
+
 lib: generatedheaders
 	$(Q)for i in $(addprefix $@/,$(TARGETS)); do \
 		if [ -d $$i ]; then \
@@ -77,7 +83,7 @@ install: lib
 doc:
 	$(Q)$(MAKE) -C doc doc
 
-clean:
+clean: cleanheaders
 	$(Q)for i in $(addprefix lib/,$(TARGETS)) \
 		     $(addsuffix /*/*,$(addprefix examples/,$(TARGETS))); do \
 		if [ -d $$i ]; then \

scripts/irq2nvic_h

@@ -130,12 +130,22 @@ def needs_update(infiles, outfiles):
     return any(not os.path.exists(o) for o in outfiles) or max(map(timestamp, infiles)) > min(map(timestamp, outfiles))
 
 def main():
+    if sys.argv[1] == '--remove':
+        remove = True
+        del sys.argv[1]
+    else:
+        remove = False
     infile = sys.argv[1]
     if not infile.startswith('./include/libopencm3/') or not infile.endswith('/irq.yaml'):
         raise ValueError("Arguent must match ./include/libopencm3/**/irq.yaml")
     nvic_h = infile.replace('irq.yaml', 'nvic.h')
     vector_nvic_c = infile.replace('./include/libopencm3/', './lib/').replace('irq.yaml', 'vector_nvic.c')
 
+    if remove:
+        os.unlink(nvic_h)
+        os.unlink(vector_nvic_c)
+        sys.exit(0)
+
     if not needs_update([__file__, infile], [nvic_h, vector_nvic_c]):
         sys.exit(0)