ethtool: bump version to 3.12.1

ethtool: bump version to 3.12.1

3.12 release notes:

	* Fix: Remove alternate method to check for VLAN tag offload on Linux
	  < 2.6.37 (-k/-K options)
	* Fix: Hide state of VLAN tag offload and LRO if the kernel is too old
	  for us to reliably detect them (-k option)
	* Feature: Add register dump support for Solarflare SFC9100 family
	  (-d option)

3.12.1 release notes:

This includes a couple of changes that should have gone into 3.12.

	* Fix: Memory corruption when applying external calibration to
	  SFF-8472 module diagnostics (-m option)
	* Feature: Add Intel 82599 and x540 DCB registers to dump
	  (-d option)

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>