oeqa/runtime/ping: don't bother trying to ping localhost

If SLIRP is being used instead of TAP for networking to the guest then
the target IP will be localhost.  There's no point in pinging localhost
to see if the target is up but whilst you'd think it is harmless, in
some containers ping doesn't actually have enough rights to work:

  ping: socktype: SOCK_RAW
  ping: socket: Operation not permitted
  ping: => missing cap_net_raw+p capability or setuid?

Look at the target address and if it's localhost or 127.0.0.* return
immediately.

(Backport from OE-Core rev: a06ef43d2a50e16c32bd6edbdc7b32c3528687d5)

(From OE-Core rev: 649147913e89cd8f7390cb17cd0be94c9710ffa6)

Signed-off-by: Michael Haener <michael.haener@siemens.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

meta/lib/oeqa/runtime/cases/ping.py

@@ -18,6 +18,13 @@ class PingTest(OERuntimeTestCase):
         output = ''
         count = 0
         self.assertNotEqual(len(self.target.ip), 0, msg="No target IP address set")
+
+        # If the target IP is localhost (because user-space networking is being used),
+        # then there's no point in pinging it.
+        if self.target.ip.startswith("127.0.0.") or self.target.ip in ("localhost", "::1"):
+            print("runtime/ping: localhost detected, not pinging")
+            return
+
         try:
             while count < 5:
                 cmd = 'ping -c 1 %s' % self.target.ip