markdownlint: fix all warnings

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I2a77806e59860015339b90957e2226eecd6b5423
diff --git a/.markdownlint.yaml b/.markdownlint.yaml
new file mode 100644
index 0000000..15c9e81
--- /dev/null
+++ b/.markdownlint.yaml
@@ -0,0 +1,3 @@
+default: true
+MD024:
+    siblings_only: true