python3: fix xattrs with musl (patch from Alpine)

See https://github.com/GNS3/gns3-gui/issues/1392.

srcpkgs/python3/patches/fix-xattrs-glibc.patch

@@ -0,0 +1,13 @@
+--- Modules/posixmodule.c.orig
++++ Modules/posixmodule.c
+@@ -103,8 +103,9 @@ corresponding Unix manual entries for more information on calls.");
+ #undef HAVE_SCHED_SETAFFINITY
+ #endif
+ 
+-#if defined(HAVE_SYS_XATTR_H) && defined(__GLIBC__) && !defined(__FreeBSD_kernel__) && !defined(__GNU__)
++#if defined(HAVE_SYS_XATTR_H) && defined(__linux__) && !defined(__FreeBSD_kernel__) && !defined(__GNU__)
+ #define USE_XATTRS
++#include <linux/limits.h>
+ #endif
+ 
+ #ifdef USE_XATTRS

srcpkgs/python3/template

@@ -1,7 +1,7 @@
 # Template file for 'python3'
 pkgname=python3
 version=3.5.4
-revision=1
+revision=2
 wrksrc="Python-${version}"
 short_desc="Interpreted, interactive, object-oriented programming language (${version%.*} series)"
 maintainer="Juan RP <xtraeme@voidlinux.eu>"