Don't continue if we cannot detect the real card type, otherwise, all
subsequent functions, especially strcpy(), would fail, leaving the whole
driver in an unusable state.

Without such a protection, dmesg would look like this:

Pid: 1525, comm: modprobe Not tainted 2.6.38-rc6 #1 MSI MS-7250/MS-7250
EIP: 0060:[<c114e700>] EFLAGS: 00010296 CPU: 1
EIP is at strcpy+0x10/0x30
EAX: f4d33e58 EBX: f5990800 ECX: f4d33e58 EDX: 00000000
ESI: 00000000 EDI: f4d33e58 EBP: f5990930 ESP: f3dd3e0c
DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
f53d4204 00000000 f90bfc03 00000001 00000001 f3dd3e64 c10fedff f3dd3e7c
f3d854e4 f53d4000 c10307b8 00000001 c10307b8 f5990860 c10307b8 00000001
c10332e5 f59908bc c12f4339 f59908bc f5990860 c11ef207 f4d33e00 f53d4000
[<f90bfc03>] ? snd_hdspm_probe+0x7e7/0x1166 [snd_hdspm]
[<c10fedff>] ? __sysfs_add_one+0x1f/0xf0
[<c10307b8>] ? get_parent_ip+0x8/0x20
[<c10307b8>] ? get_parent_ip+0x8/0x20
[<c10307b8>] ? get_parent_ip+0x8/0x20
[<c10332e5>] ? add_preempt_count+0xa5/0xd0
[<c12f4339>] ? _raw_spin_lock_irqsave+0x19/0x40
[<c11ef207>] ? pm_runtime_enable+0x17/0x80
[<c1160172>] ? local_pci_probe+0x42/0xb0
[<c1161091>] ? pci_device_probe+0x61/0x80
[<c11e9587>] ? driver_probe_device+0x77/0x180
[<c11600f0>] ? pci_match_device+0xa0/0xc0
[<c11e9709>] ? __driver_attach+0x79/0x80
[<c11e9690>] ? __driver_attach+0x0/0x80
[<c11e8e32>] ? bus_for_each_dev+0x52/0x80
[<c11e9416>] ? driver_attach+0x16/0x20
[<c11e9690>] ? __driver_attach+0x0/0x80
[<c11e8771>] ? bus_add_driver+0xa1/0x220
[<c1160f20>] ? pci_device_remove+0x0/0xf0
[<c11e99a3>] ? driver_register+0x63/0x120
[<c11612bd>] ? __pci_register_driver+0x3d/0xb0
[<c1001132>] ? do_one_initcall+0x32/0x160
[<f90d6000>] ? alsa_card_hdspm_init+0x0/0x14 [snd_hdspm]
[<c10676a9>] ? sys_init_module+0x99/0x1e0
[<c10ade3d>] ? sys_close+0x6d/0xc0
[<c1002c90>] ? sysenter_do_call+0x12/0x26
---[ end trace 239f0661c558378b ]---
Signed-off-by: NAdrian Knoth <adi@drcomp.erfurt.thur.de>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>