whoops, was doing big blob scan every time read config...
Use square brackets for substituted object id

Using normal parentheses is a bit disingenuous, you think that maybe
a human wrote that text - whereas square brackets look more
appropriately artificial, without being too intrusive. I think.

Also fits better with the tendency for people to follow a commit id
with a parenthetical summary. For instance:

Fixed up a trivial conflict in mm/memcontrol.c as per Tejun (due to
commit 7bd83da2d2 (formerly bea8c150a7) ("memcg: fix hotplugged memory zone oops") in master
touching code close to commit 1fce51a146 (formerly 2ef37d3fe4) ("memcg: Simplify
mem_cgroup_force_empty_list error handling") in for-3.8)

...looks weird because who follows parentheses with parentheses!? So
this is a bit better:

Fixed up a trivial conflict in mm/memcontrol.c as per Tejun (due to
commit 7bd83da2d2 [formerly bea8c150a7] ("memcg: fix hotplugged memory zone oops") in master
touching code close to commit 1fce51a146 [formerly 2ef37d3fe4] ("memcg: Simplify
mem_cgroup_force_empty_list error handling") in for-3.8)
Move to correct folder
tidy