Add master submodule for mysql

.gitmodules

@@ -798,3 +798,8 @@
 	url = ../url.git
 	fetchRecurseSubmodules = on-demand
 	branch = .
+[submodule "mysql"]
+	path = libs/mysql
+	url = ../mysql.git
+	fetchRecurseSubmodules = on-demand
+	branch = .

libs/mysql

@@ -0,0 +1 @@
+Subproject commit a3c9844ef3e9b81852dd782101e7c71246a4302d