bees: make a thread note when we read data

Reads can block indefinitely due to bugs, low io priority, or poor
storage performance.  Record the block origin data in the thread state
so we can see which reads are problematic.

Signed-off-by: Zygo Blaxell <bees@furryterror.org>
(cherry picked from commit f56f736d28)

src/bees-types.cc

@@ -930,6 +930,7 @@ BeesBlockData::data() const
 {
 	if (m_data.empty()) {
 		THROW_CHECK1(invalid_argument, size(), size() > 0);
+		BEESNOTE("Reading BeesBlockData " << *this);
 		BEESTOOLONG("Reading BeesBlockData " << *this);
 		Timer read_timer;