buildroot

toolchain/crosstool-NG: update to 1.13.1

crosstool-ng-1.13.1 contains a fix for the UBI breakage in
the installed kernel headers.
Refresh a patch.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>