package/boost: bump to version 1.69.0

- Remove fifth patch (already in version)
- Remove BR2_PACKAGE_BOOST_SIGNALS as signals is now removed. Its
  removal was announced in 1.68 and its deprecation was announced in
  1.54. Users are encouraged to use Signals2 instead.

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
diff --git a/Config.in.legacy b/Config.in.legacy
index 6f1e3ee..ef46075 100644
--- a/Config.in.legacy
+++ b/Config.in.legacy
@@ -146,6 +146,14 @@
 
 comment "Legacy options removed in 2019.02"
 
+config BR2_PACKAGE_BOOST_SIGNALS
+	bool "Boost signals removed"
+	select BR2_LEGACY
+	help
+	  Its removal was announced in boost 1.68 and its deprecation
+	  was announced in 1.54. Users are encouraged to use Signals2
+	  instead.
+
 config BR2_PACKAGE_LUA_5_2
 	bool "Lua 5.2.x version removed"
 	select BR2_LEGACY