firefox: fix build on big endian ppc64 with vendor nss

srcpkgs/firefox/patches/vendor-nss-ppc64-vsx.patch

@@ -0,0 +1,25 @@
+From bb8c878129e872c8a4cd3534f85486ff6c000ac2 Mon Sep 17 00:00:00 2001
+From: q66 <daniel@octaforge.org>
+Date: Thu, 7 May 2020 19:18:18 +0200
+Subject: [PATCH] fix build on non-vsx ppc64 platforms
+
+---
+ security/nss/lib/freebl/gcm.h | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git security/nss/lib/freebl/gcm.h security/nss/lib/freebl/gcm.h
+index b2c30a7..54fb3d0 100644
+--- security/nss/lib/freebl/gcm.h
++++ security/nss/lib/freebl/gcm.h
+@@ -30,7 +30,7 @@
+ #include <arm_neon.h>
+ #endif
+ 
+-#if defined(__powerpc64__) && !defined(NSS_DISABLE_ALTIVEC)
++#if defined(__powerpc64__) && defined(__VSX__) && !defined(NSS_DISABLE_ALTIVEC)
+ #include "altivec-types.h"
+ 
+ /* The ghash freebl test tries to use this in C++, and gcc defines conflict. */
+-- 
+2.25.1
+