spl: fit: Fix the number of bytes read when reading fdt from fit

sectors field is not being updated when reading fdt from fit image. Because of
this size_of(u-boot.bin) is being read when reading fdt. Fixing it by updating
the sectors field properly.
Tested-by: NMichal Simek <michal.simek@xilinx.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NTom Rini <trini@konsulko.com>
Signed-off-by: NLokesh Vutla <lokeshvutla@ti.com>

common/spl/spl_fit.c

@@ -182,6 +182,7 @@ int spl_load_simple_fit(struct spl_load_info *info, ulong sector, void *fit)
 	 */
 	dst = load_ptr + data_size;
 	fdt_offset += base_offset;
+	sectors = (fdt_len + info->bl_len - 1) / info->bl_len;
 	count = info->read(info, sector + fdt_offset / info->bl_len, sectors,
 			   dst);
 	debug("fit read %x sectors to %x, dst %p, data_offset %x\n",