Docs: Add missing RST docs

Adds dcos.rst files for all modules lacking documentation.

Change-Id: Ief5594831d31fcb876381a4a3886382fab7d595e
diff --git a/pw_log_basic/docs.rst b/pw_log_basic/docs.rst
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+.. _chapter-pw-log-basic:
+
+.. default-domain:: cpp
+
+.. highlight:: sh
+
+------------
+pw_log_basic
+------------
+``pw_log_basic`` is a ``pw_log backend`` that sends logs over ``pw_sys_io``. The
+destination of ``pw_sys_io`` depends on the ``pw_sys_io`` backend in use. This
+is controlled by the ``dir_pw_sys_io_backend`` variable in a target's
+``target_config.gni``.
+information.
+
+This module employs an internal buffer for formatting log strings, and currently
+has a fixed size of 150 bytes. Any final log statements that are larger than
+149 bytes (one byte used for a null terminator) will be truncated.
+
+.. note::
+  The documentation for this module is currently incomplete.