package/libnss: fix build failure with ARM without NEON extension

At the moment libnss assumes that every ARM has NEON extension but it's
not that way. So add a patch to make it aware of it and use native
functions in place of NEON optimized ones.

Fixes:
http://autobuild.buildroot.net/results/1342d305d1aeebef7af54a83afc094fda12421e2/

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

package/libnss/0003-Bug-1590676-Fix-build-if-arm-doesn-t-support-NEON.patch

@@ -0,0 +1,50 @@
+From c915be634cbfb90eb7880ec9efbdba9b98c6d4c1 Mon Sep 17 00:00:00 2001
+From: Giulio Benetti <giulio.benetti@benettiengineering.com>
+Date: Wed, 23 Oct 2019 11:47:03 +0200
+Subject: [PATCH] Bug 1590676 - Fix build if arm doesn't support NEON
+
+At the moment NSS assumes that ARM supports NEON extension but this is
+not true and leads to build failure on ARM without NEON extension.
+Add check to assure USE_HW_AES is not defined if ARM without NEON
+extension is used.
+
+Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
+---
+ nss/lib/freebl/aes-armv8.c | 5 +++--
+ nss/lib/freebl/rijndael.c  | 3 ++-
+ 2 files changed, 5 insertions(+), 3 deletions(-)
+
+diff --git a/nss/lib/freebl/aes-armv8.c b/nss/lib/freebl/aes-armv8.c
+index 40d5e2d34..057d1aed3 100644
+--- a/nss/lib/freebl/aes-armv8.c
++++ b/nss/lib/freebl/aes-armv8.c
+@@ -5,9 +5,10 @@
+ #include "secerr.h"
+ #include "rijndael.h"
+ 
+-#if (defined(__clang__) ||                            \
++#if ((defined(__clang__) ||                            \
+      (defined(__GNUC__) && defined(__GNUC_MINOR__) && \
+-      (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ > 8))))
++      (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ > 8)))) && \
++      (defined(__ARM_NEON) || defined(__ARM_NEON__)))
+ 
+ #ifndef __ARM_FEATURE_CRYPTO
+ #error "Compiler option is invalid"
+diff --git a/nss/lib/freebl/rijndael.c b/nss/lib/freebl/rijndael.c
+index 26bd58ee0..6d77d942d 100644
+--- a/nss/lib/freebl/rijndael.c
++++ b/nss/lib/freebl/rijndael.c
+@@ -20,7 +20,8 @@
+ #include "gcm.h"
+ #include "mpi.h"
+ 
+-#if !defined(IS_LITTLE_ENDIAN) && !defined(NSS_X86_OR_X64)
++#if (!defined(IS_LITTLE_ENDIAN) && !defined(NSS_X86_OR_X64)) || \
++    (defined(__arm__) && !defined(__ARM_NEON) && !defined(__ARM_NEON__))
+ // not test yet on big endian platform of arm
+ #undef USE_HW_AES
+ #endif
+-- 
+2.20.1
+