perf intel-pt: Prefer get_unaligned_le64 to memcpy_le64

Use get_unaligned_le64() instead of memcpy_le64(..., 8) because it produces
simpler code.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20231005190451.175568-6-adrian.hunter@intel.com


Signed-off-by: Namhyung Kim <namhyung@kernel.org>