default.xml: Bump meta-freescale revision

* 2e785f2 : Merge pull request #1139 from Freescale/backport-1138-to-kirkstone - Otavio Salvador
* ded83a4 : conf/machine/ls1046ardb.conf: Add DTB fsl-ls1046a-rdb-usdpaa-shared.dtb - Jun Zhu

Signed-off-by: Pavel Zhukov <pavel.zhukov@huawei.com>