PCI: Remove DEFINE_PCI_DEVICE_TABLE macro

Backported from hdspm to comply with kernel coding guidelines.
Use standard printk helpers

Backported from mainline kernel
Convert to snd_card_new() with a device pointer

Backported from mainline kernel.

Also remove superfluous snd_card_set_dev() call
Add patch for kernel versions below 3.15.0
Update README for kernels below 3.15.
Fix style error found by checkpatch.pl
Add LICENSE file

Copied from linux-kernel/COPYING
Add copyright statements