- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Since DELAY() was moved, most <machine/clock.h> #includes have been
unnecessary.

Fix a bunch of bugs I came accross when looking at the ixgb(4) driver,
some of which are rather serious:
- Use the device sysctl tree instead of rolling our own.
- Don't create a bus_dmamap_t to pass to bus_dmamem_alloc(), it is
bus_dmamem_alloc() that creates it itself. The DMA map created
by the driver was overwritten and its memory was leaked.
- Fix resource handling bugs in the error path of ixgb_dma_alloc().
- Don't use vtophys() to get the base address of the TX and RX rings
when busdma already gave us the correct address to use!
- Remove now useless includes and the alpha_XXX_dmamap() hack.
- Don't initialize if_output to ether_output(), ether_ifattach() does
it for us already.
- Add proper module dependencies on ether and pci.

Unfortunately, I'm not lucky enough to own an ixgb(4) card, nor a
machine with a bus where to plug it in and I couldn't find anyone able
to test these patches, so they are only build-tested and I won't MFC
them for 5.4-RELEASE.

Start each of the license/copyright comments with /*-, minor shuffle of lines

First release of ixgb driver for the Intel(R) PRO/10GbE Family of Adapters. This driver has
been developed for use with FreeBSD, version 4.8 and later.

Submitted by: Hema Joyce
Reviewed by: Prafulla Deuskar
Approved by: Prafulla Deuskar
MFC after: 1 week