tools: imximage: Fix potential memory leak

Dynamic memory, referenced by 'line', is allocated at imximage.c:761
by calling function 'getline' and lost at imximage.c:793.

Signed-off-by: Maks Mishin <maks.mishinFZ@gmail.com>

tools/imximage.c

@@ -783,6 +783,7 @@ static uint32_t parse_cfg_file(struct imx_header *imxhdr, char *name)
 	}
 
 	(*set_dcd_rst)(imxhdr, dcd_len, name, lineno);
+	free(line);
 	fclose(fd);
 
 	/* Exit if there is no BOOT_FROM field specifying the flash_offset */