perf bpf augmented_raw_syscalls: Add an assert to make sure sizeof(augmented_arg->value) is a power of two.

Similar to what was done in the previous cset for sizeof(saddr), we need
to make sure sizeof(augmented_arg->value) is a power of two to do bounds
checking using &=:

  augmented_len &= sizeof(augmented_arg->value) - 1;
Suggested-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/ZONrPo0NSqdbXiGx@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>