add valgrind instrumentation

[bratpiorka]

currently, our valgrind instrumentation is empty:

#define VALGRIND_DO_MEMPOOL_ALLOC(pool, ptr, size)                             \
    do {                                                                       \
        (void)(pool);                                                          \
        (void)(ptr);                                                           \
        (void)(size);                                                          \
    } while (0)

#define VALGRIND_DO_MEMPOOL_FREE(pool, ptr)                                    \
    do {                                                                       \
        (void)(pool);                                                          \
        (void)(ptr);                                                           \
    } while (0)
#endif

additionally, our GPU workflows should be run with all instrumentation enabled (could be done in Nightly builds)