Re: [PATCH v2] merge-recursive: change current file dir string_lists to hashmap

The code was using two string_lists, one for the directories and
one for the files.  The code never checks the lists independently
so we should be able to only use one list.  The string_list also
is a O(log n) for lookup and insertion.  Switching this to use a
hashmap will give O(1) which will save some time when there are
millions of paths that will be checked.

Also cleaned up a memory leak and method where the return was not
being used.

Signed-off-by: Kevin Willford <redacted>
---
 merge-recursive.c | 76 ++++++++++++++++++++++++++++++++++++++++---------------
 merge-recursive.h |  3 +--
 2 files changed, 57 insertions(+), 22 deletions(-)

diff --git a/merge-recursive.c b/merge-recursive.c
index 1494ffdb82..ebfe01017f 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c

@@ -24,6 +24,31 @@
 #include "dir.h"
 #include "submodule.h"
 
+struct path_hashmap_entry {
+	struct hashmap_entry;