esp8266: Implement software SPI class.
Supports speeds up to 500k baud, polarity=0/1, phase=0/1, and using any
pins. Only supports MSB output at the moment.
diff --git a/esp8266/esp8266.ld b/esp8266/esp8266.ld
index 2677668..8430195 100644
--- a/esp8266/esp8266.ld
+++ b/esp8266/esp8266.ld
@@ -133,6 +133,7 @@
*modpybpin.o(.literal*, .text*)
*modpybrtc.o(.literal*, .text*)
*modpybadc.o(.literal*, .text*)
+ *modpybspi.o(.literal*, .text*)
*modesp.o(.literal* .text*)
*modnetwork.o(.literal* .text*)
*moduos.o(.literal* .text*)