hw/misc/sifive_u_otp: handling the fails of blk_pread and blk_pwrite
Fix code coverage issues by checking return value and handling fail case
of blk_pread() and blk_pwrite(). Return default value 0xff if read fails.
Fixes: Coverity CID
1435959
Fixes: Coverity CID
1435960
Fixes: Coverity CID
1435961
Signed-off-by: Green Wan <green.wan@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id:
20201104092900.21214-1-green.wan@sifive.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>