Add Format_isValid() and Format_isEqual() to NBAIO

This is in preparation for changing the typedef to a struct.

Change-Id: I8eb1c7d98fd12f997641e462359864fdb834abe6
diff --git a/include/media/nbaio/NBAIO.h b/include/media/nbaio/NBAIO.h
index 9c9721a..468508c 100644
--- a/include/media/nbaio/NBAIO.h
+++ b/include/media/nbaio/NBAIO.h
@@ -76,6 +76,12 @@
 typedef ssize_t (*readVia_t)(void *user, const void *buffer,
                              size_t count, int64_t readPTS);
 
+// Check whether an NBAIO_Format is valid
+bool Format_isValid(const NBAIO_Format& format);
+
+// Compare two NBAIO_Format values
+bool Format_isEqual(const NBAIO_Format& format1, const NBAIO_Format& format2);
+
 // Abstract class (interface) representing a data port.
 class NBAIO_Port : public RefBase {