Fix namespace of host_ptr

[steffenlarsen]

Existing Sample Changes

Description

The device_ptr and host_ptr aliases in DPC++ is from the sycl_ext_intel_usm_address_spaces and as such is under the sycl::ext::intel namespace, rather than the sycl namespace. This commit fixes the namespaces of all uses of these aliases.

External Dependencies

None.

Type of change

• [X] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Implement fixes for ONSAM Jiras

How Has This Been Tested?

Following the build instructions in each of the respective sample directories.

• [X] Command Line
• [ ] oneapi-cli
• [ ] Visual Studio
• [ ] Eclipse IDE
• [ ] VSCode
• [ ] When compiling the compliler flag "-Wall -Wformat-security -Werror=format-security" was used

[jimmytwei]

@yuguen-intel As these are FPGA samples, can you take a look at this? @steffenlarsen Can you submit a PR to the development branch?

[steffenlarsen]

Replaced by https://github.com/oneapi-src/oneAPI-samples/pull/2291.