add hemdall install

Change-Id: I153cb95fd78eeca382814ddd28b738c65a2bb0bf
diff --git a/_samsung/samsunggalaxya23.markdown b/_samsung/samsunggalaxya23.markdown
index 764b3f4..549e315 100644
--- a/_samsung/samsunggalaxya23.markdown
+++ b/_samsung/samsunggalaxya23.markdown
@@ -21,6 +21,8 @@
 
 {% include odininstall.html %}
 
+{% include heimdallinstall.html %}
+
 {% include twrpinstall.html %}
 
 {% include appinstall.html %}