micropython: Disable for Blackfin

There are two problems building micropython for Blackfin. The first is
some printf format specifier warnings/errors that seem to be triggered
only for that architecture/compiler. This could be worked around by
specifying CFLAGS=-Wno-error=format.

The second problem is that libffi doesn't provide the closure
implementation on Blackfin. There is no known workaround for this issue.

For now disable micropython on Blackfin.

Signed-off-by: Chris Packham <judge.packham@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/micropython/Config.in

@@ -2,6 +2,8 @@ config BR2_PACKAGE_MICROPYTHON
 	bool "micropython"
 	select BR2_PACKAGE_LIBFFI
 	depends on BR2_TOOLCHAIN_HAS_THREADS
+	# libffi doesn't provide the closure implementation on Blackfin
+	depends on !BR2_bfin
 	help
 	  Micro Python is a lean and fast implementation of the Python 3
 	  programming language that is optimised to run on a microcontroller.
@@ -10,3 +12,4 @@ config BR2_PACKAGE_MICROPYTHON
 
 comment "micropython needs a toolchain w/ threads"
 	depends on !BR2_TOOLCHAIN_HAS_THREADS
+	depends on !BR2_bfin