staging: vme_user: return the appropriate error code when module_init fails

When init_module fails, 0 is returned anyway; the module is then installed
and oopses when we try to remove it:

[ 3236.368009] WARNING: at drivers/base/driver.c:262 driver_unregister+0x36/0x6f()
[ 3236.368012] Hardware name:
[ 3236.368014] Unexpected driver unregister!
[ 3236.368016] Modules linked in: vme_user(-) vme_tsi148 vme e1000e iTCO_wdt iTCO_vendor_support [last unloaded: vme]
[ 3236.368027] Pid: 16162, comm: rmmod Not tainted 2.6.35 #2
[ 3236.368029] Call Trace:
[ 3236.368037]  [<ffffffff81036ea3>] warn_slowpath_common+0x80/0x98
[ 3236.368044]  [<ffffffff81060a65>] ? __try_stop_module+0x0/0x58
[ 3236.368049]  [<ffffffff81036f4f>] warn_slowpath_fmt+0x41/0x43
[ 3236.368054]  [<ffffffff81060a65>] ? __try_stop_module+0x0/0x58
[ 3236.368059]  [<ffffffff811e8f78>] driver_unregister+0x36/0x6f
[ 3236.368066]  [<ffffffffa004aa44>] vme_unregister_driver+0xd/0xf [vme]
[ 3236.368072]  [<ffffffffa00616c8>] vme_user_exit+0x10/0x1e [vme_user]
[ 3236.368076]  [<ffffffff810612c1>] sys_delete_module+0x1ba/0x226
[ 3236.368082]  [<ffffffff812d6e14>] ? do_page_fault+0x25d/0x28a
[ 3236.368088]  [<ffffffff8100202b>] system_call_fastpath+0x16/0x1b
[ 3236.368092] ---[ end trace cab6d88ebc44c1de ]---

The appended fixes it by returning the appropriate error code in module_init
whenever something goes wrong, thus cancelling the insertion of the module.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Acked-by: Martyn Welch <martyn.welch@ge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/vme/devices/vme_user.c

@@ -611,6 +611,7 @@ static int __init vme_user_init(void)
 	if (bus_num == 0) {
 		printk(KERN_ERR "%s: No cards, skipping registration\n",
 			driver_name);
+		retval = -ENODEV;
 		goto err_nocard;
 	}
 
@@ -629,6 +630,7 @@ static int __init vme_user_init(void)
 	if (ids == NULL) {
 		printk(KERN_ERR "%s: Unable to allocate ID table\n",
 			driver_name);
+		retval = -ENOMEM;
 		goto err_id;
 	}