siimage: separate PATA and SATA methods

* Split off sil_sata_udma_filter() from sil_udma_filter()
  and rename sil_udma_filter() to sil_pata_udma_filter().

* Rename siimage_busproc() to sil_sata_busproc().

* Rename siimage_reset_poll() to sil_sata_reset_poll()
  and in init_hwif_siimage() set ->reset_poll method only
  for SATA controllers.

* Rename siimage_pre_reset() to sil_sata_pre_reset(),
  in init_hwif_siimage() set ->pre_reset method only for
  SATA controllers and remove redundant is_sata() call.

* Add CONFIG_BLK_DEV_IDE_SATA #ifdef/#endif to pdev_is_sata()
  so compiler will know to throw out unused SATA code for
  CONFIG_BLK_DEV_IDE_SATA=n case (830 bytes saved on x86-32).

* Bump driver version.

Some minor cleanups while at it:

* Convert sil_{pata,sata}_udma_filter() to use ATA_UDMA* defines.

* In siimage_mmio_ide_dma_test_irq() move 'base' variable
  under 'if (SATA_ERROR_REG)' block.

* Simplify sil_sata_reset_poll() a bit.

* Cache is_sata() result in init_hwif_siimage() 

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>