package/flac: Fix musl compile

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/flac/0002-sigemptyset.patch

@@ -0,0 +1,18 @@
+Fix musl compile since it does not define __sigemptyset
+
+Downloaded from
+http://git.alpinelinux.org/cgit/aports/commit/main/flac/sigemptyset.patch?id=49fd0f4cebc46e2753d6a60e450078446f7f18a7
+
+Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
+
+--- ./src/libFLAC/cpu.c.orig
++++ ./src/libFLAC/cpu.c
+@@ -243,7 +243,7 @@
+ 		struct sigaction sigill_save;
+ 		struct sigaction sigill_sse;
+ 		sigill_sse.sa_sigaction = sigill_handler_sse_os;
+-		__sigemptyset(&sigill_sse.sa_mask);
++		sigemptyset(&sigill_sse.sa_mask);
+ 		sigill_sse.sa_flags = SA_SIGINFO | SA_RESETHAND; /* SA_RESETHAND just in case our SIGILL return jump breaks, so we don't get stuck in a loop */
+ 		if(0 == sigaction(SIGILL, &sigill_sse, &sigill_save))
+ 		{