do_smhload: fix return code

do_smhload was using a ulong to store the return value from
smh_load_file. That returns an int, where -1 indicates an error. As a
ulong will never be negative, smh_load_file errors were not detected and
so_smhload always returned zero.

Also, when errors were spotted, do_smhload was returning 1, rather than
the enumeration CMD_RET_FAILURE (which is also 1).

Signed-off-by: Ryan Harkin <ryan.harkin@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/lib/semihosting.c

@@ -186,7 +186,7 @@ static int do_smhload(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	if (argc == 3 || argc == 4) {
 		ulong load_addr;
 		ulong end_addr = 0;
-		ulong ret;
+		int ret;
 		char end_str[64];
 
 		load_addr = simple_strtoul(argv[2], NULL, 16);
@@ -195,7 +195,7 @@ static int do_smhload(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 
 		ret = smh_load_file(argv[1], load_addr, &end_addr);
 		if (ret < 0)
-			return 1;
+			return CMD_RET_FAILURE;
 
 		/* Optionally save returned end to the environment */
 		if (argc == 4) {