Corrected the check for 'clear_persistent_files'

Previously: As a part of BMC firmware update via REST API process, "check_persistent_files" flag was being incorrectly checked. As a result persistent file system was cleaned even through  "check_persistent_files" flag was left at "0" (default)

Post-Change:  Persistent file system was cleaned only if  "check_persistent_files" flag is set to "1" by the user.
diff --git a/bin/bmc_update.py b/bin/bmc_update.py
index af1629c..a3032cf 100755
--- a/bin/bmc_update.py
+++ b/bin/bmc_update.py
@@ -103,7 +103,7 @@
 			tar.extractall(UPDATE_PATH,members=doExtract(tar,copy_files))
 			tar.close()
 
-			if (self.Get(DBUS_NAME,"clear_persistent_files") == False):
+			if (self.Get(DBUS_NAME,"clear_persistent_files") == True):
 				print "Removing persistent files"
 				os.unlink(UPDATE_PATH+"/whitelist")
 			if (self.Get(DBUS_NAME,"preserve_network_settings") == True):