Change git-svn not to impose a limit of 16 parents on a merge.
This limit in git-svn artificially prevents cloning svn repositories
that contain commits with more than 16 merge parents.
The limit was removed from builtin-commit-tree.c for git v1.6.0 in commit
ef98c5cafb3e799b1568bb843fcd45920dc62f16, so there is no need to check for it
it in git-svn.
Signed-off-by: Andrew Myrick <amyrick@apple.com>
Acked-by: Eric Wong <normalperson@yhbt.net>