meta-ibm: fix some shellcheck issues

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Iced76041c1207dc9ab28a83fd849ba3cd0a07bb5
diff --git a/meta-ibm/recipes-phosphor/chassis/vrm-control/ibm-ac-server/ir35221-unbind-bind.sh b/meta-ibm/recipes-phosphor/chassis/vrm-control/ibm-ac-server/ir35221-unbind-bind.sh
index 85d7741..c35a61b 100644
--- a/meta-ibm/recipes-phosphor/chassis/vrm-control/ibm-ac-server/ir35221-unbind-bind.sh
+++ b/meta-ibm/recipes-phosphor/chassis/vrm-control/ibm-ac-server/ir35221-unbind-bind.sh
@@ -9,7 +9,7 @@
 platform_path="/sys/devices/platform/ahb/ahb:apb/ahb:apb:bus@1e78a000/"
 
 unbind_driver () {
-    echo $1 > $driver_path/unbind
+    echo "$1" > $driver_path/unbind
 }
 
 bind_driver () {
@@ -19,7 +19,8 @@
     until [ $tries -ge $max_retries ]; do
         tries=$((tries+1))
         ret=0
-        echo $device > $driver_path/bind || ret=$?
+        # shellcheck disable=SC2320
+        echo "$device" > $driver_path/bind || ret=$?
         if [ $ret -ne 0 ]; then
             echo "VRM $1 bind failed. Try $tries"
             sleep 1
@@ -29,7 +30,7 @@
     done
 
     #Script will return a nonzero value if any binds fail.
-    if [ $ret -ne 0 ]; then
+    if [ "$ret" -ne 0 ]; then
         status=$ret
     fi
 }
@@ -78,4 +79,4 @@
     fi
 fi
 
-exit $status
+exit "$status"