fiemap: don't force flush so we can see the delalloc shenanigans

Like filefrag, fiemap was defaulting to FIEMAP_FLAG_SYNC, and providing no
option to turn it off.  This prevents observation of delayed allocations,
making fiemap less useful.

Override the default flag setting so fiemap gets the current
(i.e. unflushed) extent map state.

Signed-off-by: Zygo Blaxell <bees@furryterror.org>

src/fiemap.cc

@@ -23,6 +23,7 @@ main(int argc, char **argv)
 		cout << "File: " << filename << endl;
 		Fd fd = open_or_die(filename, O_RDONLY);
 		Fiemap fm;
+		fm.fm_flags &= ~(FIEMAP_FLAG_SYNC);
 		fm.m_max_count = 100;
 		if (argc > 2) { fm.fm_start = stoull(argv[2], nullptr, 0); }
 		if (argc > 3) { fm.fm_length = stoull(argv[3], nullptr, 0); }