uclibc: snapshots are bz2

Snapshot tarballs are only in bz2 format, fixes:
http://autobuild.buildroot.net/results/b02/b021b296309d01405ad45344055863a5761abd70/

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/uclibc/uclibc.mk

@@ -5,15 +5,15 @@
 ################################################################################
 
 UCLIBC_VERSION = $(call qstrip,$(BR2_UCLIBC_VERSION_STRING))
-UCLIBC_SOURCE = uClibc-$(UCLIBC_VERSION).tar.xz
+UCLIBC_SOURCE = uClibc-$(UCLIBC_VERSION).tar.bz2
 
 ifeq ($(BR2_UCLIBC_VERSION_SNAPSHOT),y)
 UCLIBC_SITE = http://www.uclibc.org/downloads/snapshots
 else ifeq ($(findstring arc,$(UCLIBC_VERSION)),arc)
 UCLIBC_SITE = $(BR2_ARC_SITE)
-UCLIBC_SOURCE = uClibc-$(UCLIBC_VERSION).tar.bz2
 else
 UCLIBC_SITE = http://www.uclibc.org/downloads
+UCLIBC_SOURCE = uClibc-$(UCLIBC_VERSION).tar.xz
 endif
 
 UCLIBC_INSTALL_STAGING = YES