kunit: consolidate KUNIT_INIT_BINARY_ASSERT_STRUCT macros

We currently have 2 other versions of KUNIT_INIT_BINARY_ASSERT_STRUCT.
The only differences are that
* the format funcition they pass is different
* the types of left_val/right_val should be different (integral,
pointer, string).

The latter doesn't actually matter since these macros are just plumbing
them along to KUNIT_ASSERTION where they will get type checked.

So combine them all into a single KUNIT_INIT_BINARY_ASSERT_STRUCT that
now also takes the format function as a parameter.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>