kunit: decrease macro layering for EQ/NE asserts

Introduce KUNIT_BINARY_PTR_ASSERTION to match KUNIT_BINARY_INT_ASSERTION
and make KUNIT_EXPECT_EQ and KUNIT_EXPECT_PTREQ use these instead of
shared intermediate macros that only remove the need to type "==" or
"!=".

The current macro chain looks like:
KUNIT_EXPECT_EQ_MSG => KUNIT_BINARY_EQ_MSG_ASSERTION => KUNIT_BASE_EQ_MSG_ASSERTION => KUNIT_BASE_BINARY_ASSERTION
KUNIT_EXPECT_PTR_EQ_MSG => KUNIT_BINARY_PTR_EQ_MSG_ASSERTION => KUNIT_BASE_EQ_MSG_ASSERTION => KUNIT_BASE_BINARY_ASSERTION
<ditto for NE and ASSERT>

After this change:
KUNIT_EXPECT_EQ_MSG => KUNIT_BINARY_INT_ASSERTION => KUNIT_BASE_BINARY_ASSERTION
KUNIT_EXPECT_PTR_EQ_MSG => KUNIT_BINARY_PTR_ASSERTION => KUNIT_BASE_BINARY_ASSERTION

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>