Remove hip-hcc codes: Part three

1.Rename include/hip/hcc_detail/ as include/hip/amd_detail/

2.Rename include/hip/nvcc_detail/ as include/hip/nvidia_detail/

3.Create __HIP_PLATFORM_AMD__ to replace __HIP_PLATFORM_HCC__

4.Create __HIP_PLATFORM_NVIDIA__ to replace __HIP_PLATFORM_NVCC__

After hcc_detail, nvcc_detail, __HIP_PLATFORM_HCC__ and __HIP_PLATFORM_NVCC__
have been removed from upstream, they will be removed from hip runtime.

Change-Id: I1ae457effd739d6c25bca203c1724b026be21fce

samples/0_Intro/square/square.hipref.cpp

@@ -57,7 +57,7 @@ int main(int argc, char* argv[]) {
     hipDeviceProp_t props;
     CHECK(hipGetDeviceProperties(&props, device /*deviceID*/));
     printf("info: running on device %s\n", props.name);
-#ifdef __HIP_PLATFORM_HCC__
+#ifdef __HIP_PLATFORM_AMD__
     printf("info: architecture on AMD GPU device is: %s\n", props.gcnArchName);
 #endif
     printf("info: allocate host mem (%6.2f MB)\n", 2 * Nbytes / 1024.0 / 1024.0);