Add serial port bitbanging code

This adds the pony_spi driver which supports the SI_Prog adapter, which
is commonly used for SPI chips with PonyProg 2000, and a custom adapter
called "SERBANG" which differs in the logic of two pins.

Corresponding to flashrom svn r1525.

Signed-off-by: Virgil-Adrian Teaca <darkstarlinux@gmail.com>
Acked-by: Michael Karcher <flashrom@mkarcher.dialup.fu-berlin.de>
diff --git a/flashrom.c b/flashrom.c
index c60b46e..a54348d 100644
--- a/flashrom.c
+++ b/flashrom.c
@@ -201,6 +201,16 @@
 	},
 #endif
 
+#if CONFIG_PONY_SPI == 1
+	{
+		.name			= "pony_spi",
+		.init			= pony_spi_init,
+		.map_flash_region	= fallback_map,
+		.unmap_flash_region	= fallback_unmap,
+		.delay			= internal_delay,
+},
+#endif
+
 #if CONFIG_NICINTEL == 1
 	{
 		.name			= "nicintel",