uboot-omap: update to 2015.10

uboot-omap: update to 2015.10

- tested on Beagleboard C4

- remove upstream patches

- disable THUMB mode on OMAP3 this increases binary size
  (remove CONFIG_SYS_THUMB_BUILD)
- reduce SPL size by disabling EXT feature
  (remove CONFIG_SPL_EXT_SUPPORT)

this fixes 2015.07 and 2015.10-rc3
Beagleboard C4 booting
which were broken by upstream commit
with id: bd2c4522c26d535515aebca52d27c004a7e0c05c

Arm THUMB mode is broken because of an yet unknown errata
see: http://lists.denx.de/pipermail/u-boot/2015-August/225793.html

- backport upstream fix that was introduced in 2015.10-rc5
  and was not fixed in 2015.10 final

Signed-off-by: Dirk Neukirchen <dirkneukirchen@web.de>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@47924 3c298f89-4303-0410-b956-a3cf2f4a3e73