recovery init: fix device name

"i" variable in the nested loop is expanded to the absolute path
of the device, so prepending it with the ${device} results in
"/dev/sda/dev/sda1" for a 'sda1' partition.

Signed-off-by: Javier Viguera <javier.viguera@digi.com>

meta-digi-dey/recipes-core/recovery/recovery-initramfs/recovery-initramfs-init

@@ -158,7 +158,7 @@ mount_external_disks() {
 	local devices=$(ls -1 /dev/sd? 2>/dev/null)
 	for device in ${devices}; do
 		for i in ${device}?; do
-			local dev_name=$(basename "${device}${i}")
+			local dev_name=$(basename "${i}")
 			local mount_dir="${USB_MOUNT_DIR}${dev_name}"
 			mkdir -p "${mount_dir}"
 			mount "/dev/${dev_name}" "${mount_dir}" 2>/dev/null