package/rtorrent: disable execinfo

Disable execinfo to avoid the following build failure raised since the
addition of libexecinfo package in commit
eea8ba446c10701a273432552108d80fb2224ef4:

/home/giuliobenetti/autobuild/run/instance-0/output-1/host/lib/gcc/arc-buildroot-linux-uclibc/10.2.0/../../../../arc-buildroot-linux-uclibc/bin/ld: main.o: in function `do_panic(int)':
/home/giuliobenetti/autobuild/run/instance-0/output-1/build/rtorrent-0.9.8/src/main.cc:606: undefined reference to `backtrace'

Fixes:
 - http://autobuild.buildroot.org/results/10fc9016013931c58238240216c5950b23b56b30

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/rtorrent/0001-Added--disable-execinfo-option-to-configure.patch

@@ -0,0 +1,34 @@
+From 582e4e40256b43d3e5322168f1e1ed71ca70ab64 Mon Sep 17 00:00:00 2001
+From: rakshasa <sundell.software@gmail.com>
+Date: Wed, 16 Jun 2021 23:29:01 +0900
+Subject: [PATCH] Added '--disable-execinfo' option to configure.
+
+[Retrieved (and backported) from:
+https://github.com/rakshasa/rtorrent/commit/582e4e40256b43d3e5322168f1e1ed71ca70ab64]
+Signed-off-by: Fabrice Fontaine <Fontaine.fabrice@gmail.com>
+---
+ configure.ac | 11 ++++++++++-
+ 1 file changed, 10 insertions(+), 1 deletion(-)
+
+diff --git a/configure.ac b/configure.ac
+index e3e7d3f1..0f45bc6a 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -27,7 +27,15 @@ TORRENT_WITHOUT_VARIABLE_FDSET
+ 
+ AC_SYS_LARGEFILE
+ 
+-TORRENT_CHECK_EXECINFO
++AC_ARG_ENABLE(execinfo,
++  AC_HELP_STRING([--disable-execinfo], [disable libexecinfo [[default=enable]]]),
++  [
++    if test "$enableval" = "yes"; then
++      TORRENT_CHECK_EXECINFO
++    fi
++  ],[
++    TORRENT_CHECK_EXECINFO
++  ])
+ 
+ TORRENT_ENABLE_ARCH
+ TORRENT_WITH_SYSROOT
+ 

package/rtorrent/rtorrent.mk

@@ -9,5 +9,8 @@ RTORRENT_SITE = http://rtorrent.net/downloads
 RTORRENT_DEPENDENCIES = host-pkgconf libcurl libtorrent ncurses
 RTORRENT_LICENSE = GPL-2.0
 RTORRENT_LICENSE_FILES = COPYING
+# We're patching configure.ac
+RTORRENT_AUTORECONF = YES
+RTORRENT_CONF_OPTS = --disable-execinfo
 
 $(eval $(autotools-package))