Reindent some comments
Most (older) comments in md.c and smgr.c are indented with a leading
tab on all lines, which isn't the current style and makes updating the
comments a bit annoying. This reindents all these lines with a single
space, as is the normal style. This issue exists in various shapes
throughout the code but it's pretty consistent here, and since there
is a patch pending to refresh some of the comments in these files, it
seems sensible to clean this up here separately.
Discussion: https://www.postgresql.org/message-id/flat/
22fed8ba-01c3-2008-a256-
4ea912d68fab%40enterprisedb.com