places-setup: fix unlink warnings

Signed-off-by: Varun Patil <radialapps@gmail.com>

lib/Service/Places.php

@@ -97,10 +97,14 @@ class Places
         flush();
 
         $filename = sys_get_temp_dir().'/planet_coarse_boundaries.zip';
-        unlink($filename);
+        if (file_exists($filename) && !unlink($filename)) {
+            throw new \Exception("Failed to delete old planet zip file: $filename");
+        }
 
         $txtfile = sys_get_temp_dir().'/planet_coarse_boundaries.txt';
-        unlink($txtfile);
+        if (file_exists($txtfile) && !unlink($txtfile)) {
+            throw new \Exception("Failed to delete old planet data file: $txtfile");
+        }
 
         $fp = fopen($filename, 'w+');
 
@@ -130,7 +134,7 @@ class Places
         }
 
         // Delete zip file
-        unlink($filename);
+        @unlink($filename);
 
         return $txtfile;
     }
@@ -329,7 +333,7 @@ class Places
         $this->config->setSystemValue('memories.gis_type', $gis);
 
         // Delete data file
-        unlink($datafile);
+        @unlink($datafile);
     }
 
     /**