Merge pull request ERGO-Code#2259 from ERGO-Code/mpopcnt

Do not add mpopcnt to nvcc

Author: jajhall

CMakeLists.txt

@@ -400,12 +400,13 @@ if (NOT HIGHS_COVERAGE AND NOT APPLE)
   if(CMAKE_SYSTEM_PROCESSOR MATCHES "^(ppc64|powerpc64)")
       check_cxx_compiler_flag("-mpopcntd" COMPILER_SUPPORTS_POPCNTD)
       if(COMPILER_SUPPORTS_POPCNTD)
-          set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mpopcntd")
+          # set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mpopcntd")
+          add_compile_options("$<$<COMPILE_LANGUAGE:CXX>:-mpopcntd>")
       endif()
   else()
       check_cxx_compiler_flag("-mpopcnt" COMPILER_SUPPORTS_POPCNT)
       if(COMPILER_SUPPORTS_POPCNT)
-          add_compile_options(-mpopcnt)
+          add_compile_options("$<$<COMPILE_LANGUAGE:CXX>:-mpopcnt>")
       endif()
   endif()
 endif()