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Remove alternative C++ operator

Created by: KOVI89alipes

Hi, One of the HLS template files uses old-style, alternative logical C++ operator and and not

https://github.com/fastmachinelearning/hls4ml/blob/c3509cfeb5f80054e01dead612392a9411ebfbe2/hls4ml/templates/vivado/nnet_utils/nnet_mult.h#L93

template<class data_T, class res_T, typename CONFIG_T>
inline typename std::enable_if<std::is_same<data_T, ap_uint<1>>::value
        and std::is_same<typename CONFIG_T::weight_t, ap_uint<1>>::value, ap_int<nnet::ceillog2(CONFIG_T::n_in) + 2>>::type
cast(typename CONFIG_T::accum_t x){
  return (ap_int<nnet::ceillog2(CONFIG_T::n_in) + 2>) (x - CONFIG_T::n_in / 2) * 2;
}

template<class data_T, class res_T, typename CONFIG_T>
inline typename std::enable_if<(not std::is_same<data_T, ap_uint<1>>::value), res_T>::type
cast(typename CONFIG_T::accum_t x){
  return (res_T) x;
}

These are alternative tokens https://en.cppreference.com/w/cpp/language/operator_alternative

And they are not supported by the MSVC compiler https://stackoverflow.com/questions/24414124/why-does-vs-not-define-the-alternative-tokens-for-logical-operators

It prevents HLS4ML kernel code to be compiled in Windows with MSVC and gives an error

firmware\nnet_utils\nnet_mult.h(88): error C2146: syntax error: missing '>' before identifier 'and'

Suggestion: replace alternative logical operators with standard ones and -> &&, not->~

template<class data_T, class res_T, typename CONFIG_T>
inline typename std::enable_if<std::is_same<data_T, ap_uint<1>>::value
        && std::is_same<typename CONFIG_T::weight_t, ap_uint<1>>::value, ap_int<nnet::ceillog2(CONFIG_T::n_in) + 2>>::type
cast(typename CONFIG_T::accum_t x){
  return (ap_int<nnet::ceillog2(CONFIG_T::n_in) + 2>) (x - CONFIG_T::n_in / 2) * 2;
}

template<class data_T, class res_T, typename CONFIG_T>
inline typename std::enable_if<(! std::is_same<data_T, ap_uint<1>>::value), res_T>::type
cast(typename CONFIG_T::accum_t x){
  return (res_T) x;
}

Code with these changes can be compiled in MSVC and is still valid in GCC, Vivado HLS

Why to bother - we are using HLS4ML kernels in Windows and it's nice to have bittrue model of the kernel for verification purposes.