fixing bugs in kubespray install script

Change-Id: I770d51d3df34040eb2a1929de77431fdc4fb38d1
diff --git a/kubespray-installer/setup.sh b/kubespray-installer/setup.sh
index 0d1b25f..aab3986 100755
--- a/kubespray-installer/setup.sh
+++ b/kubespray-installer/setup.sh
@@ -39,7 +39,7 @@
   then
     virtualenv ks_venv
     pip install ansible==2.5.3
-    pip install -f kubespray/kubespray/requirements.txt
+    pip install -r kubespray/requirements.txt
   fi
 
   # shellcheck disable=SC1091