scripts/rpc: allow server address to be a relative path

Change-Id: I93f7e4e7d76f2fac4174050b249329993f28f71f
Signed-off-by: Karol Latecki <karol.latecki@intel.com>
Reviewed-on: https://review.gerrithub.io/c/442095
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Chandler-Test-Pool: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Pawel Wodkowski <pawelx.wodkowski@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Paweł Niedźwiecki <pawelx.niedzwiecki@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>

scripts/rpc/client.py

@@ -1,6 +1,7 @@
 import json
 import socket
 import time
+import os
 
 
 def print_dict(d):
@@ -18,7 +19,7 @@ class JSONRPCClient(object):
         self.timeout = timeout
         self.request_id = 0
         try:
-            if addr.startswith('/'):
+            if os.path.exists(addr):
                 self.sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
                 self.sock.connect(addr)
             elif ':' in addr: