Add OpenVDB (and sub libraries) the new way

deps/OpenVDB/OpenVDB.cmake

@@ -0,0 +1,38 @@
+if(BUILD_SHARED_LIBS)
+    set(_build_shared ON)
+    set(_build_static OFF)
+else()
+    set(_build_shared OFF)
+    set(_build_static ON)
+endif()
+
+prusaslicer_add_cmake_project(OpenVDB
+    GIT_REPOSITORY https://github.com/AcademySoftwareFoundation/openvdb.git
+    GIT_TAG aebaf8d95be5e57fd33949281ec357db4a576c2e #v6.2.1
+    DEPENDS dep_TBB dep_Blosc dep_OpenEXR #dep_Boost
+    PATCH_COMMAND       ${GIT_EXECUTABLE} reset --hard && ${GIT_EXECUTABLE} clean -df &&
+                        ${GIT_EXECUTABLE} apply --whitespace=nowarn ${CMAKE_CURRENT_LIST_DIR}/openvdb-mods.patch
+    CMAKE_ARGS
+        -DCMAKE_POSITION_INDEPENDENT_CODE=ON 
+        -DOPENVDB_BUILD_PYTHON_MODULE=OFF
+        -DUSE_BLOSC=ON
+        -DOPENVDB_CORE_SHARED=${_build_shared} 
+        -DOPENVDB_CORE_STATIC=${_build_static}
+        -DOPENVDB_ENABLE_RPATH:BOOL=OFF
+        -DTBB_STATIC=${_build_static}
+        -DOPENVDB_BUILD_VDB_PRINT=ON
+        -DDISABLE_DEPENDENCY_VERSION_CHECKS=ON # Centos6 has old zlib
+)
+
+if (MSVC)
+    if (${DEP_DEBUG})
+        ExternalProject_Get_Property(dep_OpenVDB BINARY_DIR)
+        ExternalProject_Add_Step(dep_OpenVDB build_debug
+            DEPENDEES build
+            DEPENDERS install
+            COMMAND ${CMAKE_COMMAND} ../dep_OpenVDB -DOPENVDB_BUILD_VDB_PRINT=OFF
+            COMMAND msbuild /m /P:Configuration=Debug INSTALL.vcxproj
+            WORKING_DIRECTORY "${BINARY_DIR}"
+        )
+    endif ()
+endif ()