drivers/char/rtc: disable legacy RTC driver on Blackfin systems

Blackfin platforms do not support the hardware which this driver drives.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David Brownell <david-b@pacbell.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/char/Kconfig

@@ -807,7 +807,7 @@ if RTC_LIB=n
 config RTC
 	tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
 	depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
-			&& !ARM && !SUPERH && !S390 && !AVR32
+			&& !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN
 	---help---
 	  If you say Y here and create a character special file /dev/rtc with
 	  major number 10 and minor number 135 using mknod ("man mknod"), you