uboot: fix hash for 2015.10 version

Commit bf2bd1132128175362cba26d80d8ef4216b2c32c bumped U-Boot to version
2015.10 but forgot to update the hash as well.

Signed-off-by: Jörg Krause <joerg.krause@embedded.rocks>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

boot/uboot/uboot.hash

@@ -1,2 +1,2 @@
 # Locally computed:
-sha256	0b48c9bd717f2c322ef791f8282e14c88be942dc7d1226df7e31a812a3af94d9  u-boot-2015.07.tar.bz2
+sha256  bdc68d5f9455ad933b059c735d983f2c8b6b552dafb062e5ff1444f623021955  u-boot-2015.10.tar.bz2