Change VG_(DebugInfo_sect_kind) to return a pointer to the name
via its first parameter instead of copying into a fixed size buffer.
The so returned name should be saved away if needed sometime later.
Where "sometime later" means that a debuginfo could be discarded in
the meantime. This is currently not the case. But the subtlety is
commented on.


git-svn-id: svn://svn.valgrind.org/valgrind/branches/BUF_REMOVAL@14445 a5019735-40e9-0310-863c-91ae7b9d1cf9
Allocate SectKind.objname dynamically.


git-svn-id: svn://svn.valgrind.org/valgrind/branches/BUF_REMOVAL@14446 a5019735-40e9-0310-863c-91ae7b9d1cf9