tools: imximage: Fix check array index

tools: imximage: Fix check array index

The struct dcd_v1_t is initialized to MAX_HW_CFG_SIZE_V1 (60)
 structs 'dcd_type_addr_data_t', so the indexes to use on its elements
 are [0,59]. But on line 478, the variable 'length' can take on the value
 60, which applies to array overflow: cd_v1->addr_data[length].type Thus,
 it is necessary to tighten the check on the 'size' variable on line 463.

Fixes: 0b0c6af38738 ("Prepare v2020.01")
Signed-off-by: Mikhail Ilin <ilin.mikhail.ol@gmail.com>