libflash/libffs: Correctly update the actual size of the partition

libffs has been updating FFS partition information in the wrong place
which leads to incomplete erases and corruption.

Fixes: 602dee4 libflash/libffs: Rework libffs
Signed-off-by: Cyril Bur <cyril.bur@au1.ibm.com>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>

libflash/libffs.c

@@ -781,7 +781,7 @@ int ffs_update_act_size(struct ffs_handle *ffs, uint32_t part_idx,
 		FL_DBG("FFS: Entry not found\n");
 		return FFS_ERR_PART_NOT_FOUND;
 	}
-	offset = ent->base;
+	offset = ffs->toc_offset + ffs_hdr_raw_size(part_idx);
 	FL_DBG("FFS: part index %d at offset 0x%08x\n",
 	       part_idx, offset);