use the tools found during bootstrap

Makefile

@@ -33,30 +33,30 @@ chapter_codecs: $(OUTPUT_CHAPTER_CODECS).html $(OUTPUT_CHAPTER_CODECS).txt $(OUT
 control: $(OUTPUT_CONTROL).html $(OUTPUT_CONTROL).txt $(OUTPUT_CONTROL).xml
 
 matroska_xsd.xml: transforms/schema_clean.xsl ebml_matroska.xml
-	xsltproc transforms/schema_clean.xsl ebml_matroska.xml > $@
+	$(XSLTPROC_CALL) transforms/schema_clean.xsl ebml_matroska.xml > $@
 
 control_xsd.xml: transforms/schema_clean_control.xsl ebml_matroska.xml
-	xsltproc transforms/schema_clean_control.xsl ebml_matroska.xml > $@
+	$(XSLTPROC_CALL) transforms/schema_clean_control.xsl ebml_matroska.xml > $@
 
 check: matroska_xsd.xml control_xsd.xml $(EBML_SCHEMA_XSD)
-	xmllint --version
-	xmllint --noout --schema $(EBML_SCHEMA_XSD) matroska_xsd.xml
-	xmllint --noout --schema $(EBML_SCHEMA_XSD) control_xsd.xml
+	$(XMLLINT_CALL) --version
+	$(XMLLINT_CALL) --noout --schema $(EBML_SCHEMA_XSD) matroska_xsd.xml
+	$(XMLLINT_CALL) --noout --schema $(EBML_SCHEMA_XSD) control_xsd.xml
 
 ebml_matroska_elements4rfc.md: transforms/ebml_schema2markdown4rfc.xsl matroska_xsd.xml
-	xsltproc transforms/ebml_schema2markdown4rfc.xsl matroska_xsd.xml > $@
+	$(XSLTPROC_CALL) transforms/ebml_schema2markdown4rfc.xsl matroska_xsd.xml > $@
 
 matroska_iana_ids.md: transforms/ebml_schema2markdown4iana_ids.xsl matroska_xsd.xml
-	xsltproc transforms/ebml_schema2markdown4iana_ids.xsl matroska_xsd.xml > $@
+	$(XSLTPROC_CALL) transforms/ebml_schema2markdown4iana_ids.xsl matroska_xsd.xml > $@
 
 matroska_iana.xml: transforms/ebml_schema2xml4iana_ids.xsl matroska_xsd.xml
-	xsltproc transforms/ebml_schema2xml4iana_ids.xsl matroska_xsd.xml | sed -e "s/@BUILD_DATE@/$(shell date +'%F')/"  > $@
+	$(XSLTPROC_CALL) transforms/ebml_schema2xml4iana_ids.xsl matroska_xsd.xml | sed -e "s/@BUILD_DATE@/$(shell date +'%F')/"  > $@
 
 matroska_deprecated4rfc.md: transforms/ebml_schema2markdown4deprecated.xsl matroska_xsd.xml
-	xsltproc transforms/ebml_schema2markdown4deprecated.xsl matroska_xsd.xml > $@
+	$(XSLTPROC_CALL) transforms/ebml_schema2markdown4deprecated.xsl matroska_xsd.xml > $@
 
 control_elements4rfc.md: transforms/ebml_schema2markdown4rfc.xsl control_xsd.xml
-	xsltproc transforms/ebml_schema2markdown4rfc.xsl control_xsd.xml > $@
+	$(XSLTPROC_CALL) transforms/ebml_schema2markdown4rfc.xsl control_xsd.xml > $@
 
 $(OUTPUT_MATROSKA).md: index_matroska.md diagram.md matroska_schema_section_header.md ebml_matroska_elements4rfc.md ordering.md notes.md chapters.md attachments.md cues.md streaming.md tags-precedence.md matroska_implement.md matroska_security.md iana_matroska_ids.md matroska_iana_ids.md iana.md rfc_backmatter_matroska.md matroska_annex.md matroska_deprecated4rfc.md
 	cat $^ | sed -e "s/@BUILD_DATE@/$(shell date +'%F')/" \
@@ -89,10 +89,10 @@ $(OUTPUT_CONTROL).md: index_control.md control.md control_elements4rfc.md menu.m
 	$(XML2RFC) $< -o $@
 
 matroska_tagging_registry.md: matroska_tags.xml transforms/matroska_tags2markdown4rfc.xsl
-	xsltproc transforms/matroska_tags2markdown4rfc.xsl $< > $@
+	$(XSLTPROC_CALL) transforms/matroska_tags2markdown4rfc.xsl $< > $@
 
 tags_iana_names.md: matroska_tags.xml transforms/matroska_tags2markdown4iana.xsl
-	xsltproc transforms/matroska_tags2markdown4iana.xsl $< > $@
+	$(XSLTPROC_CALL) transforms/matroska_tags2markdown4iana.xsl $< > $@
 
 website:
 	jekyll b