imximage: Fix imximage IVT bug for EIM-NOR boot

The load region size of EIM-NOR are defined to 0. For this case,
the parameter "imximage_init_loadsize" must be calculated.
The imximage tool implements the calculation in the "imximage_generate"
function, but the following function "imximage_set_header" resets the value
and not calculate. This bug cause some fields of IVT head are not
correct, for example the boot_data and DCD overlay the application area.

Signed-off-by: Ye.Li <B37916@freescale.com>
diff --git a/tools/imximage.c b/tools/imximage.c
index 18dc051..faba238 100644
--- a/tools/imximage.c
+++ b/tools/imximage.c
@@ -568,6 +568,13 @@
 	/* Parse dcd configuration file */
 	dcd_len = parse_cfg_file(imxhdr, params->imagename);
 
+	if (imximage_version == IMXIMAGE_V2) {
+		if (imximage_init_loadsize < imximage_ivt_offset +
+			sizeof(imx_header_v2_t))
+				imximage_init_loadsize = imximage_ivt_offset +
+					sizeof(imx_header_v2_t);
+	}
+
 	/* Set the imx header */
 	(*set_imx_hdr)(imxhdr, dcd_len, params->ep, imximage_ivt_offset);