contrib: add yaml rules

Change-Id: I6c3a186949c9b152208bfea1bc663f24229f1ff1
Refs: #46617

contrib/src/yaml/SHA512SUMS

+be80c85360663dbf64b1adf60f725c08ff5589379858b22c089b1fa33b29083898d651bb260c16a14128425ca4a26dc7701fafb12937632bf75f9b15615a260c  yaml-0.1.5.tar.gz

contrib/src/yaml/rules.mak

+# YAML
+YAML_VERSION := 0.1.5
+YAML_URL := http://pyyaml.org/download/libyaml/yaml-$(YAML_VERSION).tar.gz
+
+PKGS += yaml
+
+$(TARBALLS)/yaml-$(YAML_VERSION).tar.gz:
+	$(call download,$(YAML_URL))
+
+.sum-yaml: yaml-$(YAML_VERSION).tar.gz
+
+yaml: yaml-$(YAML_VERSION).tar.gz .sum-yaml
+	$(UNPACK)
+	$(MOVE)
+
+.yaml: yaml
+	$(RECONF)
+	cd $< && $(HOSTVARS) ./configure $(HOSTCONF)
+	cd $< && $(MAKE) install
+	touch $@