externals: Track mainline inih project

.gitmodules

@@ -1,6 +1,6 @@
 [submodule "inih"]
     path = externals/inih/inih
-    url = https://github.com/svn2github/inih
+    url = https://github.com/benhoyt/inih.git
 [submodule "cubeb"]
     path = externals/cubeb
     url = https://github.com/kinetiknz/cubeb.git