Upgrade libevent to release-2.1.11-stable

Test: None
Change-Id: Ic8d8dbcc23eb124f36f9cf0f6427751b2a460067
diff --git a/configure.ac b/configure.ac
index e644034..298d3ab 100644
--- a/configure.ac
+++ b/configure.ac
@@ -5,8 +5,8 @@
 dnl
 dnl Original version Dug Song <dugsong@monkey.org>
 
-AC_INIT(libevent,2.1.10-stable)
-AC_PREREQ(2.59)
+AC_INIT(libevent,2.1.11-stable)
+AC_PREREQ(2.62)
 AC_CONFIG_SRCDIR(event.c)
 
 AC_CONFIG_MACRO_DIR([m4])
@@ -14,7 +14,7 @@
 dnl AM_SILENT_RULES req. automake 1.11.  [no] defaults V=1
 m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
 AC_CONFIG_HEADERS(config.h  evconfig-private.h:evconfig-private.h.in)
-AC_DEFINE(NUMERIC_VERSION, 0x02010a00, [Numeric representation of the version])
+AC_DEFINE(NUMERIC_VERSION, 0x02010b00, [Numeric representation of the version])
 
 dnl Initialize prefix.
 if test "$prefix" = "NONE"; then