Update doc/README.md

Fixed 2 broken links to files in ./doc

Author: cyberman54

doc/README.md

@@ -4,7 +4,7 @@ This directory contains documentation on the use and implementation of the LMIC.
 
 ## Usage documentation
 
-- [`LMIC-v3.0.99.pdf`](./LoRaWAN-v3.0.99.pdf): API documentation on the LMIC as of 3.0.99. Generally the differences between 3.0.99 and 3.2 were bug fixes.
+- [`LMIC-v3.0.99.pdf`](./LMIC-v3.0.99.pdf): API documentation on the LMIC as of 3.0.99. Generally the differences between 3.0.99 and 3.2 were bug fixes.
 
 ## Background information
 
@@ -13,7 +13,7 @@ This directory contains documentation on the use and implementation of the LMIC.
 ## Implementation documentation
 
 - [`RadioDriver.md`](./RadioDriver.md): documentation of the radio driver interface.
-- [`LMIC-structure.pdf`](./LMIC-structure.pdf): a structural diagram of the LMIC. This is somewhat UML like.
+- [`LMIC-structure-diagram.pdf`](./LMIC-structure-diagram.pdf): a structural diagram of the LMIC. This is somewhat UML like.
 - [`LMIC-FSM.pdf`](./LMIC-FSM.pdf): the operating logic of the LMIC, modeled as a finite state machine. As of version 3.2, this model is idealized; the actual implementation is not an explicit state machine. However, if you search for `os_setCallback()` and `os_setTimedCallback()`, you will see the links between event callbacks, and that will generally correspond to the implementation.  The FSM diagram doesn't show class-B or class-C operation as yet.
 
 ## Historical information