WIP: unify the RAK targets into one firmware (#1350)

* First steps to unify GPS Lib for RAK 1910 and RAK 12500

* Technicalities. Out with the old and build the new.

* Adapt Matrix

* We use 0.4.5 now

* While we're at it, yank the RAK815, it's EOL

* Satisfy CI - for now

* - yank UBX library, talk to GPS chip with NMEA only.
- more autodetect going on, this time for the Eink Display.

TODO: actually do something with the scan findings.

* i swear this works on windows! :-)

* these are only there to make CI happy

* don't update eink display if not detected.

* Replace Oberon Crypt Library with modified Adafruit Library. This elimintaes the need for the sdk-nfxlib submodule.

* - Revert auto screen selection (incomplete)
- Revert nrF crypto engine (needs more work)
- add separate defines for not-auto-selecting screen lib.

* Define 2 new variants for RAK - with or without epaper

* Update variants

Co-authored-by: Sacha Weatherstone <sachaw100@hotmail.com>
Co-authored-by: Ben Meadors <thebentern@tuta.io>

variants/rak4631_epaper/variant.cpp

@@ -0,0 +1,46 @@
+/*
+  Copyright (c) 2014-2015 Arduino LLC.  All right reserved.
+  Copyright (c) 2016 Sandeep Mistry All right reserved.
+  Copyright (c) 2018, Adafruit Industries (adafruit.com)
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the GNU Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#include "variant.h"
+#include "wiring_constants.h"
+#include "wiring_digital.h"
+#include "nrf.h"
+
+const uint32_t g_ADigitalPinMap[] =
+	{
+		// P0
+		0, 1, 2, 3, 4, 5, 6, 7,
+		8, 9, 10, 11, 12, 13, 14, 15,
+		16, 17, 18, 19, 20, 21, 22, 23,
+		24, 25, 26, 27, 28, 29, 30, 31,
+
+		// P1
+		32, 33, 34, 35, 36, 37, 38, 39,
+		40, 41, 42, 43, 44, 45, 46, 47};
+
+void initVariant()
+{
+	// LED1 & LED2
+	pinMode(PIN_LED1, OUTPUT);
+	ledOff(PIN_LED1);
+
+	pinMode(PIN_LED2, OUTPUT);
+	ledOff(PIN_LED2);
+}