sshfs: use SSHFS_VERSION variable in URL

Signed-off-by: Jerzy Grzegorek <jerzy.grzegorek@trzebnica.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/sshfs/sshfs.mk

@@ -5,7 +5,7 @@
 ################################################################################
 
 SSHFS_VERSION = 2.5
-SSHFS_SITE = https://github.com/libfuse/sshfs/releases/download/sshfs_2_5
+SSHFS_SITE = https://github.com/libfuse/sshfs/releases/download/sshfs_$(subst .,_,$(SSHFS_VERSION))
 SSHFS_SOURCE = sshfs-fuse-$(SSHFS_VERSION).tar.gz
 SSHFS_LICENSE = GPLv2
 SSHFS_LICENSE_FILES = COPYING