kernel headers: bump 2.6.25.x version

toolchain/kernel-headers/Config.in

@@ -137,6 +137,6 @@ config BR2_DEFAULT_KERNEL_HEADERS
 	default "2.6.22.10"	if BR2_KERNEL_HEADERS_2_6_22
 	default "2.6.23"	if BR2_KERNEL_HEADERS_2_6_23
 	default "2.6.24.7"	if BR2_KERNEL_HEADERS_2_6_24
-	default "2.6.25.5"	if BR2_KERNEL_HEADERS_2_6_25
+	default "2.6.25.6"	if BR2_KERNEL_HEADERS_2_6_25
 	default "2.6"		if BR2_KERNEL_HEADERS_SNAP