add dfu support for at91 sam9260 based boards

add dfu supprt for at91 sam9260 based boards. The USB gadget driver is ported from linux:
c94e289f195e: usb: gadget: remove incorrect __init/__exit annotations

it drops a lot of checkpatch warnings/errors:

checkpatch.pl found 12 error(s), 28 warning(s), 38 checks(s)

but for further updates I did not fix them.
The errors are all from this sort:

error: drivers/usb/gadget/at91_udc.c,87: space prohibited before open square bracket '['

a lot of "line over 80 characters" warnings ...

remove the patch, which introduced BIT() macro. Instead fix this now in the linux driver.

I had an issue with tftp on the smartweb board with current mainline (commit efde6a579fe: "Prepare v2015.10-rc3") tftp doesn;t work anymore, it stopped with:

TFTP error: 'Unsupported option(s) requested' (8)

[U-Boot,v3,1/9] net: Revert "tftp: adjust settings to be suitable for 100Mbit ethernet"
https://patchwork.ozlabs.org/patch/511761/

solved this issue. So this patch is needed for the smartweb board support.

Changes in v5:
- add comment from Andreas Biessmann:
remove BIT() usage in driver, also removed patch which introduced it for U-Boot
- rebase with current mainline
commit efde6a579fe: "Prepare v2015.10-rc3"

Changes in v4:
- rebase after taurus board changes

Changes in v3:
- add comments from Alexandre Belloni
get rid of cpu_is_at91*, use newer linux version as base for the port to U-Boot.
- adapt changes for U-Boot, as newer linux version is used.

Changes in v2:
- add comments from Lukasz Majewski
- seperate usb gadget driver port from linux into 2 commits
- first patch original from linux (with complete commit message)
- second adds U-Boot changes without "#ifdef __UBOOT__"
- new in version 2, contains U-Boot changes
- rebase to bd48c0617b5c7212e5bf22169e716da878842da4
- fix changes introduced through commit:
01acd6abbdd5: usb: USB download gadget and functions config options coherent naming
- add comments from Lukasz Majewski <[email protected]>
- use SZ_X defines

Heiko Schocher (3):
usb: gadget: at91_udc: port linux driver at91_udc
usb: gadget: at91_udc: add at91_udc into U-Boot at91, taurus, smartweb: add dfu support

 board/siemens/smartweb/smartweb.c |   29 +
 board/siemens/taurus/taurus.c     |   27 +
 drivers/usb/gadget/Makefile       |    1 +
 drivers/usb/gadget/at91_udc.c     | 1625 +++++++++++++++++++++++++++++++++++++
 drivers/usb/gadget/at91_udc.h     |  171 ++++
 include/configs/smartweb.h        |   53 +-
 include/configs/taurus.h          |   30 +-
 include/linux/usb/at91_udc.h      |   20 +
 8 files changed, 1941 insertions(+), 15 deletions(-)
 create mode 100644 drivers/usb/gadget/at91_udc.c
 create mode 100644 drivers/usb/gadget/at91_udc.h
 create mode 100644 include/linux/usb/at91_udc.h

2.1.0