Update ACL pin to 4d9687e70e2d71097cd43929d5f63377c3c44523
Update ACL pin to 4d9687e70e2d71097cd43929d5f63377c3c44523

Signed-off-by: Nikhil Raj <70dde441576cd8b053dd4c3a595f3f0b9c7a63a3@arm.com>
Change-Id: Ib6d10096a5348f06d744c5629eb3b41f9c187059

ARM-software/armnn,ARM-software/armnn,ARM-software/armnn