Relocate platform specific drivers (#13894)

* Relocate platform specific drivers

* Move stm eeprom

* Tidy up slightly

platforms/chibios/drivers/analog.h

@@ -0,0 +1,41 @@
+/* Copyright 2019 Drew Mills
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include "quantum.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct {
+    uint16_t input;
+    uint8_t  adc;
+} adc_mux;
+#define TO_MUX(i, a) \
+    (adc_mux) { i, a }
+
+int16_t analogReadPin(pin_t pin);
+int16_t analogReadPinAdc(pin_t pin, uint8_t adc);
+adc_mux pinToMux(pin_t pin);
+
+int16_t adc_read(adc_mux mux);
+
+#ifdef __cplusplus
+}
+#endif