Fix serial management in "gnirehtet rt"

The command "gnirehtet rt" first checks whether the app is installed on
the device, and installs it if necessary.

However, it didn't forward the serial parameter, so calling "gnirehtet
rt 12345678" failed to install the application on the selected device
when several were plugged.

Therefore, forward the serial to apk_require_installed().

gnirehtet

@@ -102,9 +102,10 @@ apk_install() {
 }
 
 apk_require_installed() {
+    local serial="$1"
     if [[ ! "$(eval $(adbs "$serial") shell pm list packages com.genymobile.gnirehtet)" ]]
     then
-        apk_install
+        apk_install "$serial"
         # wait a bit after the app is installed so that intent actions are correctly registered
         sleep 0.5
     fi
@@ -118,17 +119,8 @@ apk_uninstall() {
 
 start() {
     echo 'Starting gnirehtet...'
-    local dns=
-    eval set -- $(getopt d: "$@")
-    while true;
-    do
-        case "$1" in
-            -d) dns="$2"; shift 2;;
-            --) shift; break;;
-            *)  break;;
-        esac
-    done
     local serial="$1"
+    local dns="$2"
     evalv $(adbs "$serial") reverse tcp:31416 tcp:31416
     [[ $? = 0 ]] || return
     local dparam=
@@ -146,6 +138,20 @@ relay() {
     evalv "'$JAVA'" -jar "$(get_relay_path)"
 }
 
+parse_start_args() {
+    dns=
+    eval set -- $(getopt d: "$@")
+    while true;
+    do
+        case "$1" in
+            -d) dns="$2"; shift 2;;
+            --) shift; break;;
+            *)  break;;
+        esac
+    done
+    serial="$1"
+}
+
 case "$1" in
 install)
     shift
@@ -155,7 +161,8 @@ uninstall)
     apk_uninstall "$@";;
 start)
     shift
-    start "$@";;
+    parse_start_args "$@"
+    start "$serial" "$dns";;
 stop)
     shift
     stop "$@";;
@@ -164,9 +171,10 @@ relay)
     relay "$@";;
 rt)
     shift
-    apk_require_installed
+    parse_start_args "$@"
+    apk_require_installed "$serial"
     trap stop INT
-    start "$@"
+    start "$serial" "$dns"
     relay;;
 *)
     syntax;;