scons: use python3-compatible print()

These changes were generated using python's `2to3` tool.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102852
Reported-by: Alex Granni <liviuprodea@yahoo.com>
Signed-off-by: Eric Engestrom <eric.engestrom@imgtec.com>
Reviewed-by: Jose Fonseca <jfonseca@vmware.com>

src/SConscript

@@ -30,7 +30,7 @@ def write_git_sha1_h_file(filename):
         try:
             subprocess.Popen(args, stdout=f).wait()
         except:
-            print "Warning: exception in write_git_sha1_h_file()"
+            print("Warning: exception in write_git_sha1_h_file()")
             return
 
     if not os.path.exists(filename) or not filecmp.cmp(tempfile, filename):