Add kernel submodules

diff --git a/kernel/2.6.33 b/kernel/2.6.33
new file mode 160000 (submodule)
index 0000000..4a70475
--- /dev/null
+++ b/kernel/2.6.33
@@ -0,0 +1 @@
+Subproject commit 4a7047510e6bc78f2623fdc47f7ff138f44f7a43

diff --git a/kernel/2.6.33-rt b/kernel/2.6.33-rt
new file mode 160000 (submodule)
index 0000000..df1889a
--- /dev/null
+++ b/kernel/2.6.33-rt
@@ -0,0 +1 @@
+Subproject commit df1889adaa1910ab8c86644cee2934ad93c5678a