dyninst submodule + non-papi build fix (#8)

* dyninst submodule + non-papi build fix
* Fix to checkout_git_submodule
* Append CMAKE_PREFIX_PATH with /opt/rocm

.gitmodules

@@ -7,3 +7,6 @@
 [submodule "external/elfio"]
 	path = external/elfio
 	url = https://github.com/jrmadsen/ELFIO.git
+[submodule "external/dyninst"]
+	path = external/dyninst
+	url = https://github.com/jrmadsen/dyninst.git