shairport-sync: update to v2.8.1

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

sound/shairport-sync/Makefile

@@ -9,7 +9,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=shairport-sync
-PKG_VERSION:=2.8.0
+PKG_VERSION:=2.8.1
 PKG_RELEASE:=1
 
 PKG_SOURCE_PROTO:=git