add librt dependency

package/alsa-utils/Makefile

@@ -9,7 +9,7 @@ PKG_RELEASE:=		1
 PKG_MD5SUM:=		b65e9a04181bd7c9db7667a4566f8dc3
 PKG_DESCR:=		ALSA mixer utility
 PKG_SECTION:=		multimedia
-PKG_DEPENDS:=		alsa-lib libpthread libgcc
+PKG_DEPENDS:=		alsa-lib libpthread libgcc librt
 PKG_BUILDDEP:=		alsa-lib
 PKG_URL:=		http://www.alsa-project.org/
 PKG_SITES:=		ftp://ftp.alsa-project.org/pub/utils/