codeparser: Only load the codeparser cache once

The server state gets reset multiple times during startup and currently
we reload the codeparser cache each time. This is pointless and causes
unnecessary interaction time with bitbake.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

lib/bb/codeparser.py

@@ -144,6 +144,10 @@ def newShellCacheLine(self, execs):
         return cacheline
 
     def init_cache(self, d):
+        # Check if we already have the caches
+        if self.pythoncache:
+            return
+
         MultiProcessCache.init_cache(self, d)
 
         # cachedata gets re-assigned in the parent