chore(docs): Fix remaining warnings/errors

Documentation/bluetooth/ess.rst

@@ -17,7 +17,7 @@ If :ref:`bsec_api` is enabled the following additional estimates are available:
  - Indoor air quality (IAQ estimate
  - Equivalent CO2 (eCO2) estimate
 
-Please refer to :ref:`bme680` for more information about BSEC.
+Please refer to :py:mod:`bme680` for more information about BSEC.
 
 
 If notifcations are enabled a measurement of all values is performed every 3 seconds. For each measurement a notification is sent for the characteristics which have notifications enabled.

Documentation/pycardium/png.rst

 ``png`` - PNG Decoder
-===============
+=====================
 The ``png`` module provides functions to decode PNG files into raw pixel data
 which can be displayed using the card10's display or its LEDs.
 

epicardium/epicardium.h

@@ -2631,7 +2631,7 @@ API(API_BLE_SET_MODE, void epic_ble_set_mode(bool bondable, bool scanner));
 /**
  * Retrieve a scan report from the queue of scan reports.
  *
- * :param struct epic_scan_report* rpt: Pointer where the report will be stored.
+ * :param struct\ epic_scan_report* rpt: Pointer where the report will be stored.
  *
  * :return: ``0`` on success or a negative value if an error occured. Possible
  *    errors:

epicardium/modules/stream.h

@@ -11,6 +11,7 @@
 #include "queue.h"
 #else
 typedef unsigned int size_t;
+typedef int bool;
 typedef void *QueueHandle_t;
 #endif /* __SPHINX_DOC */