common: Remove invalid endianess conversion

do_bootm_standanlone() calls ntohl(images->ep) which is wrong because
endianess conversion has already been done:

do_bootm()
\-do_bootm_states()
  +-bootm_find_os()
  | \-images.ep = image_get_ep();
  |   \-uimage_to_cpu(hdr->ih_ep);
  \-boot_selected_os()
    \-do_bootm_standanlone()

Without this conversion the code works correctly at least on AT91SAM9G45.
On big endian systems there should be no difference after applying this
patch because uimage_to_cpu(x) and ntohl(x) both expand to 'x'.
Signed-off-by: NChristian Eggers <ceggers@gmx.de>

common/cmd_bootm.c

@@ -514,8 +514,8 @@ static int do_bootm_standalone(int flag, int argc, char * const argv[],
 		setenv_hex("filesize", images->os.image_len);
 		return 0;
 	}
-	appl = (int (*)(int, char * const []))(ulong)ntohl(images->ep);
-	(*appl)(argc, argv);
+	appl = (int (*)(int, char * const []))images->ep;
+	appl(argc, argv);
 	return 0;
 }