Hi,

A community patch [1] is about to be merged to main which will change the
detection of the MLX5 DevX libraries in Windows, DPDK will no longer look for
the lib and inc folders using the env variables DEVX_INC_PATH/DEVX_LIB_PATH.

Instead the user will provide the path to those folders either in the build
command line using -Dc_args and -Dc_link_args, see example below:
        -I<include_directory>
        -L<library_directory>

 "C:\Program Files\Meson\meson.exe" setup --buildtype debug
"-Dc_args=-I\"%DEVX_INC_PATH%\"" "-Dc_link_args=-L\"%DEVX_LIB_PATH%\"" build

Another option is to Use CFLAGS/LDFLAGS

Please change your compilations scripts in iol-x86_64-unit-testing to continue
compiling mlx5 as part of the supported PMDs on Windows by using one of the
ways stated above, not changing it will skip mlx5 as seen in the said patch CI
results on Windows/clang [2].

[1] -
https://patches.dpdk.org/project/dpdk/patch/20230302132150.3330288-2-thomas@monjalon.net/

[2] - https://lab.dpdk.org/results/dashboard/patchsets/25595/