Add support for -Wno-deprecated-gpu-targets

[jstrzebonski]

The flag -Wno-deprecated-gpu-targets seems to be ignored, here's a snippet from the compilation of DARMA-tasking/vt:

$ /usr/bin/ccache /nvcc_wrapper/build/nvcc_wrapper \
  -DFMT_HEADER_ONLY=1 -DFMT_USE_USER_DEFINED_LITERALS=0 \
  -DHAS_DETECTION_COMPONENT=1 -I/vt/lib/fmt -I/vt/lib/CLI -I/vt/lib/libfort/lib -Idebug -I/vt/src \
  -isystem /build/checkpoint/install/include -isystem /build/detector/install/include -Wall -pedantic -Wshadow \
  -Wno-unknown-pragmas -Wsign-compare -ftemplate-backtrace-limit=100 \
  -Wno-deprecated-gpu-targets -g -fdiagnostics-color=always -fPIC -fopenmp -std=c++14 \
  -MD -MT examples/callback/CMakeFiles/callback.dir/Unity/unity_0_cxx.cxx.o \
  -MF examples/callback/CMakeFiles/callback.dir/Unity/unity_0_cxx.cxx.o.d \
  -o examples/callback/CMakeFiles/callback.dir/Unity/unity_0_cxx.cxx.o \
  -c examples/callback/CMakeFiles/callback.dir/Unity/unity_0_cxx.cxx

nvcc warning : The 'compute_35', 'compute_37', 'compute_50', 'sm_35', 'sm_37' and 'sm_50' architectures are deprecated, and may be removed in a future release (Use -Wno-deprecated-gpu-targets to suppress warning).

As you can see, even though the flag is present, the compiler still complains about deprecated architectures.

This PR fixes the problem.

[dalg24-jenkins]

Can one of the admins verify this patch?

[masterleinad]

This looks OK to me but is it intentional that you don't specify the GPU architecture you wan't to compile for but use the default one (which turns out to be deprecated)?

[PhilMiller]

Yeah, we're using this in the context of quieting CI scripts for code that's 100% host side, but needs to not confuse nvcc as it passes through.

[dalg24]

OK to test

[DavidPoliakoff]

Sure