makepanda: Don't look for macOS framework when cross-compiling

Backport of 7191fb1ed68e470cdc7b11f3b5b74544991caea0

makepanda/makepandacore.py

@@ -1831,7 +1831,7 @@ def SmartPkgEnable(pkg, pkgconfig = None, libs = None, incs = None, defs = None,
             DefSymbol(target_pkg, d, v)
         return
 
-    elif not custom_loc and GetHost() == "darwin" and framework != None:
+    elif not custom_loc and GetHost() == "darwin" and GetTarget() == "darwin" and framework is not None:
         prefix = SDK["MACOSX"]
         if (os.path.isdir(prefix + "/Library/Frameworks/%s.framework" % framework) or
             os.path.isdir(prefix + "/System/Library/Frameworks/%s.framework" % framework) or