Revert "mailinfo: Remove only one set of square brackets"

This reverts commit 650d30d8a120c8982309ccb9ef40432b4ea2eb74.

Some mailing lists are configured add prefix "[listname] " to all their
messages, and also people hand-edit subject lines, be it an output from
format-patch or a patch generated by some other means.

We cannot stop people from mucking with the subject line, and with the
change, there always will be need for hand editing the subject when that
happens.  People have depended on the leading [bracketed string] removal.
diff --git a/builtin-mailinfo.c b/builtin-mailinfo.c
index fb5ad70..92637ac 100644
--- a/builtin-mailinfo.c
+++ b/builtin-mailinfo.c
@@ -221,8 +221,6 @@
 {
 	char *pos;
 	size_t remove;
-	int brackets_removed = 0;
-
 	while (subject->len) {
 		switch (*subject->buf) {
 		case 'r': case 'R':
@@ -237,15 +235,10 @@
 			strbuf_remove(subject, 0, 1);
 			continue;
 		case '[':
-			/* remove only one set of square brackets */
-			if (brackets_removed)
-				break;
-
 			if ((pos = strchr(subject->buf, ']'))) {
 				remove = pos - subject->buf;
 				if (remove <= (subject->len - remove) * 2) {
 					strbuf_remove(subject, 0, remove + 1);
-					brackets_removed = 1;
 					continue;
 				}
 			} else
diff --git a/t/t5100/info0012 b/t/t5100/info0012
index 9cd1415..ac1216f 100644
--- a/t/t5100/info0012
+++ b/t/t5100/info0012
@@ -1,5 +1,5 @@
 Author: Dmitriy Blinov
 Email: bda@mnsspb.ru
-Subject: [Navy-patches] Изменён список пакетов необходимых для сборки
+Subject: Изменён список пакетов необходимых для сборки
 Date: Wed, 12 Nov 2008 17:54:41 +0300
 
diff --git a/t/t5100/sample.mbox b/t/t5100/sample.mbox
index 3a757d7..c3074ac 100644
--- a/t/t5100/sample.mbox
+++ b/t/t5100/sample.mbox
@@ -514,7 +514,7 @@
 Content-Type: text/plain;
   charset=utf-8
 Content-Transfer-Encoding: 8bit
-Subject: [PATCH] [Navy-patches]
+Subject: [Navy-patches] [PATCH]
 	=?utf-8?b?0JjQt9C80LXQvdGR0L0g0YHQv9C40YHQvtC6INC/0LA=?=
 	=?utf-8?b?0LrQtdGC0L7QsiDQvdC10L7QsdGF0L7QtNC40LzRi9GFINC00LvRjyA=?=
 	=?utf-8?b?0YHQsdC+0YDQutC4?=