Update buildroot to 2020.11-rc2 (#995)

Signed-off-by: Stefan Agner <stefan@agner.ch>

buildroot/package/bitcoin/0001-src-randomenv.cpp-fix-build-on-uclibc.patch

@@ -0,0 +1,48 @@
+From 330cb33985d0ce97c20f4a0f0bbda0fbffe098d4 Mon Sep 17 00:00:00 2001
+From: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+Date: Mon, 9 Nov 2020 21:18:40 +0100
+Subject: [PATCH] src/randomenv.cpp: fix build on uclibc
+
+Check for HAVE_STRONG_GETAUXVAL or HAVE_WEAK_GETAUXVAL before using
+getauxval to avoid a build failure on uclibc
+
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+[Upstream status: https://github.com/bitcoin/bitcoin/pull/20358]
+---
+ src/randomenv.cpp | 6 +++---
+ 1 file changed, 3 insertions(+), 3 deletions(-)
+
+diff --git a/src/randomenv.cpp b/src/randomenv.cpp
+index 07122b7f6..5e07c3db4 100644
+--- a/src/randomenv.cpp
++++ b/src/randomenv.cpp
+@@ -53,7 +53,7 @@
+ #include <sys/vmmeter.h>
+ #endif
+ #endif
+-#ifdef __linux__
++#if defined(HAVE_STRONG_GETAUXVAL) || defined(HAVE_WEAK_GETAUXVAL)
+ #include <sys/auxv.h>
+ #endif
+ 
+@@ -326,7 +326,7 @@ void RandAddStaticEnv(CSHA512& hasher)
+     // Bitcoin client version
+     hasher << CLIENT_VERSION;
+ 
+-#ifdef __linux__
++#if defined(HAVE_STRONG_GETAUXVAL) || defined(HAVE_WEAK_GETAUXVAL)
+     // Information available through getauxval()
+ #  ifdef AT_HWCAP
+     hasher << getauxval(AT_HWCAP);
+@@ -346,7 +346,7 @@ void RandAddStaticEnv(CSHA512& hasher)
+     const char* exec_str = (const char*)getauxval(AT_EXECFN);
+     if (exec_str) hasher.Write((const unsigned char*)exec_str, strlen(exec_str) + 1);
+ #  endif
+-#endif // __linux__
++#endif // HAVE_STRONG_GETAUXVAL || HAVE_WEAK_GETAUXVAL
+ 
+ #ifdef HAVE_GETCPUID
+     AddAllCPUID(hasher);
+-- 
+2.28.0
+