powerpc/boot: Fix missing check of lseek() return value

This is detected by Coverity scan: CID: 1440481

Signed-off-by: Bo YU <tsu.yubo@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Bo YU 2018-10-30 09:21:55 -04:00 • committed by Michael Ellerman
commit 5d085ec04a