Build issue with OMP requirement

[caxwl]

Hi

Encountered an error during build amgx/src/classical/interpolators/distance1.cu (338): error: identifier "omp_get_max_threads" is undefined

Build env is: gcc/9.3.0 openmpi/4.1.3 cuda/11.8.0 cmake/3.24.3 cmake -DCUDA_ARCH="70" -DCMAKE_C_COMPILER=gcc -DCMAKE_CXX_COMPILER=g++ ..

Resolved the issue with inclusion of #include <omp.h> in distance1.cu header

[mattmartineau]

Thanks Wei - I never saw this issue before. I'll try reproducing and push out a fix.