uvol: fix list output on LVM backend

'uvol list' was broken when introducing support for the hidden volumes.
Fix that by not using 'continue' keyword to break the loop (as that
lead to skipping 'json_select ..') and using if-clause instead.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
(cherry picked from commit 1337c44026)

utils/uvol/files/lvm.sh

@@ -320,17 +320,18 @@ listvols() {
 			lv_mode="${lv_name:0:2}"
 			lv_name="${lv_name:3}"
 			lv_size=${lv_size%B}
-			[ "${lv_name:0:1}" = "." ] && continue
-			if [ "$json_output" = "1" ]; then
-				[ "$json_notfirst" = "1" ] && echo ","
-				echo -e "\t{"
-				echo -e "\t\t\"name\": \"$lv_name\","
-				echo -e "\t\t\"mode\": \"$lv_mode\","
-				echo -e "\t\t\"size\": $lv_size"
-				echo -n -e "\t}"
-				json_notfirst=1
-			else
-				echo "$lv_name $lv_mode $lv_size"
+			if [ "${lv_name:0:1}" != "." ]; then
+				if [ "$json_output" = "1" ]; then
+					[ "$json_notfirst" = "1" ] && echo ","
+					echo -e "\t{"
+					echo -e "\t\t\"name\": \"$lv_name\","
+					echo -e "\t\t\"mode\": \"$lv_mode\","
+					echo -e "\t\t\"size\": $lv_size"
+					echo -n -e "\t}"
+					json_notfirst=1
+				else
+					echo "$lv_name $lv_mode $lv_size"
+				fi
 			fi
 			json_select ..
 		done