toolchain/gcc: bump snapshot version

Bump default snapshot gcc version to 4.8-20120429 so that it is newer
than our latest supported version (4.7.0 release).

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

toolchain/gcc/Config.in

@@ -45,7 +45,7 @@ config BR2_GCC_SUPPORTS_FINEGRAINEDMTUNE
 
 config BR2_GCC_SNAP_DATE
 	string "GCC snapshot date"
-	default "4.7-20110430"
+	default "4.8-20120429"
 	depends on BR2_GCC_VERSION_SNAP
 	help
 	  Enter snapshot date to use for gcc.