Docs: Add missing RST docs

Adds dcos.rst files for all modules lacking documentation.

Change-Id: Ief5594831d31fcb876381a4a3886382fab7d595e
diff --git a/pw_build/docs.rst b/pw_build/docs.rst
index ce8d5e5..147c691 100644
--- a/pw_build/docs.rst
+++ b/pw_build/docs.rst
@@ -22,7 +22,7 @@
 Beyond just compiling code, Pigweed’s GN build system can also:
 
 * Generate HTML documentation, via our Sphinx integration (with ``pw_docgen``)
-* Display memory usage report cards (with pw_bloat)
+* Display memory usage report cards (with ``pw_bloat``)
 * Incrementally run unit tests after code changes (with ``pw_target_runner``)
 * And more!
 
@@ -38,7 +38,7 @@
 declarations that are used by upstream Pigweed to set some architecture-agnostic
 compiler defaults. (See Pigweed's ``//BUILDCONFIG.gn``)
 
-pw_build also provides several useful GN templates that are used throughout
+``pw_build`` also provides several useful GN templates that are used throughout
 Pigweed.
 
 Templates