nftables: fix supression of "permission denied" errors

nftables: fix supression of "permission denied" errors

Introduction of batch support broke displaying of EPERM since those are
generated by the kernel before batch processing starts and thus have the
sequence number of the NFNL_MSG_BATCH_BEGIN message instead of the
command messages. Also only a single error message is generated for the
entire batch.

This patch fixes this by noting the batch sequence number and displaying
the error for all commands since this is what would happen if the
permission check was inside batch processing as every other check.

Signed-off-by: Patrick McHardy <kaber@trash.net>