Re-enable disabled oneDNN integer layer tests

[aobolensk]

The issue was detected with clang-tidy in PR #241

Integer types were set to float as well. As a result, 3 tests in test/single_layer/test_ewlayer_onednn.cpp were disabled:

relu_int
linear_int
multidim_tensor_relu_int

The goal is to fix the root cause and re-enable the tests back with correctly selected type