LU-14617 utils: llog_reader updatelog support

LU-14617 utils: llog_reader updatelog support

The patch adds printing UPDATE_REC for llog_reader. It is usefull
for updatelog analyze. Here is an example of record

 [0x50001a21b:0x1233d:0x0] type:xattr_set/7 params:3 p_0:0 p_1:1 p_2:2
 [0x50001a211:0x475:0x0] type:xattr_set/7 params:3 p_0:0 p_1:1 p_2:2
 [0x3800182e3:0x475:0x0] type:xattr_set/7 params:3 p_0:0 p_1:1 p_2:2
 [0x200032c9a:0x245:0x0] type:xattr_set/7 params:3 p_0:0 p_1:1 p_2:2
 [0x200000001:0x15:0x0] type:write/12 params:2 p_0:3 p_1:4
 p_0 - 12/trusted.lov
 p_1 - 0/
 p_2 - 25972/\x0100000000000000000000000000000000000000000002000...
 p_3 - 25974/\x0800000000000000P\xD1AB006x0000000400EC^\x000000...
 p_4 - 1/

llog logic processing base on incrementing record index,
the fix adds checks for it. Also adds more info from header,
and drops useless - Bit X not set.

Lustre-change: https://review.whamcloud.com/43343
Lustre-commit: 9962d6f84db5fd587bbe13640a9361c2872f3728

Test-Parameters: trivial
Signed-off-by: Alexander Boyko <alexander.boyko@hpe.com>
Change-Id: Id50de15040526dc07ae708ac5db046832706be31
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/46756
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>