Blackfin: Remove

The architecture is currently unmaintained, remove.

Cc: Benjamin Matthews <mben12@gmail.com>
Cc: Chong Huang <chuang@ucrobotics.com>
Cc: Dimitar Penev <dpn@switchfin.org>
Cc: Haitao Zhang <hzhang@ucrobotics.com>
Cc: I-SYST Micromodule <support@i-syst.com>
Cc: M.Hasewinkel (MHA) <info@ssv-embedded.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Martin Strubel <strubel@section5.ch>
Cc: Peter Meerwald <devel@bct-electronic.com>
Cc: Sonic Zhang <sonic.adi@gmail.com>
Cc: Valentin Yakovenkov <yakovenkov@niistt.ru>
Cc: Wojtek Skulski <info@skutek.com>
Cc: Wojtek Skulski <skulski@pas.rochester.edu>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/post/post.c b/post/post.c
index 4194edb..8c2c822 100644
--- a/post/post.c
+++ b/post/post.c
@@ -474,7 +474,7 @@
  */
 unsigned long post_time_ms(unsigned long base)
 {
-#if defined(CONFIG_PPC) || defined(CONFIG_BLACKFIN) || defined(CONFIG_ARM)
+#if defined(CONFIG_PPC) || defined(CONFIG_ARM)
 	return (unsigned long)lldiv(get_ticks(), get_tbclk() / CONFIG_SYS_HZ)
 		- base;
 #else