timemory submodule (#1)

- library now wraps fork() to warn about fork + OpenMPI

[ROCm/rocprofiler-systems commit: fc7cc1e68f]

projects/rocprofiler-systems/.gitmodules

@@ -0,0 +1,6 @@
+[submodule "external/timemory"]
+	path = external/timemory
+	url = https://github.com/NERSC/timemory.git
+[submodule "external/perfetto"]
+	path = external/perfetto
+	url = https://android.googlesource.com/platform/external/perfetto