package/pipewire: fix build on powerpc

Fix the following build failure raised since bump to version 0.3.39 in
commit d9796f2db9866060b916487784b046bb6b76f9b6:

In file included from /home/giuliobenetti/autobuild/run/instance-1/output-1/host/powerpc-buildroot-linux-uclibc/sysroot/usr/include/signal.h:318,
                 from ../spa/include/spa/utils/defs.h:34,
                 from ../spa/include/spa/utils/type.h:32,
                 from ../spa/include/spa/support/log.h:34,
                 from ../spa/plugins/support/cpu.c:37:
../spa/plugins/support/cpu.c: In function 'impl_init':
../spa/plugins/support/cpu.c:88:33: error: called object is not a function or function pointer
   88 | #define impl_cpu_zero_denormals NULL
      |                                 ^~~~

Fixes:
 - http://autobuild.buildroot.org/results/eaf255c46b10cbb6b8a629bc15acf7772d5e274b

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

package/pipewire/0001-cpu-fix-compilation-on-some-architectures.patch

@@ -0,0 +1,28 @@
+From 651f0decea5f83730c271e9bed03cdd0048fcd49 Mon Sep 17 00:00:00 2001
+From: Wim Taymans <wtaymans@redhat.com>
+Date: Thu, 21 Oct 2021 11:09:48 +0200
+Subject: [PATCH] cpu: fix compilation on some architectures
+
+[Retrieved from:
+https://gitlab.freedesktop.org/pipewire/pipewire/-/commit/651f0decea5f83730c271e9bed03cdd0048fcd49]
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+---
+ spa/plugins/support/cpu.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/spa/plugins/support/cpu.c b/spa/plugins/support/cpu.c
+index ee1816512..01cff4854 100644
+--- a/spa/plugins/support/cpu.c
++++ b/spa/plugins/support/cpu.c
+@@ -270,7 +270,7 @@ impl_init(const struct spa_handle_factory *factory,
+ 		if ((str = spa_dict_lookup(info, SPA_KEY_CPU_VM_TYPE)) != NULL)
+ 			this->vm_type = atoi(str);
+ 		if ((str = spa_dict_lookup(info, SPA_KEY_CPU_ZERO_DENORMALS)) != NULL)
+-			impl_cpu_zero_denormals(this, spa_atob(str));
++			spa_cpu_zero_denormals(&this->cpu, spa_atob(str));
+ 	}
+ 
+ 	spa_log_debug(this->log, "%p: count:%d align:%d flags:%08x",
+-- 
+GitLab
+