README: remove stale reference to span-lite

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I390f4abd653fa1e67f715fc39e2d4695ad18071a
diff --git a/README.md b/README.md
index 93c76b4..2ebbd28 100644
--- a/README.md
+++ b/README.md
@@ -52,19 +52,6 @@
 make install
 ```
 
-#### Building span-lite
-
-Check out the [span-lite source](https://github.com/martinmoene/span-lite).
-
-Then run these commands in the source directory.
-
-```
-mkdir build && cd build
-cmake ..
-make
-make install
-```
-
 #### Building stdplus
 
 Check out the [stdplus source](https://github.com/openbmc/stdplus).