[cppcheck] Pass CMAKE_BUILD_PARALLEL_LEVEL to cppcheck.

scripts/cmake/CppCheck.cmake

@@ -2,6 +2,12 @@ if(NOT CPPCHECK_TOOL_PATH)
     return()
 endif()
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+set(CPPCHECK_PARALLEL 4)
+if(DEFINED ENV{CMAKE_BUILD_PARALLEL_LEVEL})
+    set(CPPCHECK_PARALLEL $ENV{CMAKE_BUILD_PARALLEL_LEVEL})
+elseif(DEFINED CMAKE_BUILD_PARALLEL_LEVEL)
+    set(CPPCHECK_PARALLEL ${CMAKE_BUILD_PARALLEL_LEVEL})
+endif()
 configure_file(${PROJECT_SOURCE_DIR}/scripts/test/cppcheck.in.sh ${PROJECT_BINARY_DIR}/cppcheck.sh)
 
 if(DEFINED ENV{NUM_THREADS})

scripts/test/cppcheck.in.sh

@@ -6,7 +6,7 @@ ${CPPCHECK_TOOL_PATH} \
         --std=c++17 \
         --enable=all \
         --inconclusive \
-        -j 4 \
+        -j ${CPPCHECK_PARALLEL} \
         --suppress=*:*/usr/local\* \
         --suppress=*:*ThirdParty\* \
         --suppress=*:*Tests\* \