tmux: update to 3.2

- switch to $(AUTORELEASE)
- change dependency from libevent2 to libevent2-core

Signed-off-by: Maxim Storchak <m.storchak@gmail.com>

utils/tmux/patches/100-add-crosscompiling-fallbacks.patch

@@ -0,0 +1,24 @@
+commit bb6242675ad0c7447daef148fffced882e5b4a61
+Author: Nicholas Marriott <nicholas.marriott@gmail.com>
+Date:   Thu Apr 15 06:45:19 2021 +0100
+
+    Add crosscompiling fallbacks, from Hasso Tepper.
+
+--- a/configure.ac
++++ b/configure.ac
+@@ -163,6 +163,7 @@ AC_RUN_IFELSE([AC_LANG_PROGRAM(
+ 		[return (reallocarray(NULL, 1, 1) == NULL);]
+ 	)],
+ 	AC_MSG_RESULT(yes),
++	[AC_LIBOBJ(reallocarray) AC_MSG_RESULT([no])],
+ 	[AC_LIBOBJ(reallocarray) AC_MSG_RESULT([no])]
+ )
+ AC_MSG_CHECKING([for working recallocarray])
+@@ -171,6 +172,7 @@ AC_RUN_IFELSE([AC_LANG_PROGRAM(
+ 		[return (recallocarray(NULL, 1, 1, 1) == NULL);]
+ 	)],
+ 	AC_MSG_RESULT(yes),
++	[AC_LIBOBJ(recallocarray) AC_MSG_RESULT([no])],
+ 	[AC_LIBOBJ(recallocarray) AC_MSG_RESULT([no])]
+ )
+