Blackfin arch: Advertise GENERIC_GPIO and remove duplicated GENERIC_CALIBRATE_DELAY

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>

diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig
index 017defa..5c1e215 100644
--- a/arch/blackfin/Kconfig
+++ b/arch/blackfin/Kconfig
@@ -57,7 +57,7 @@
 	bool
 	default n
 
-config GENERIC_CALIBRATE_DELAY
+config GENERIC_GPIO
 	bool
 	default y