ath5k: update dependencies

- Use config symbol defined in the driver instead of arch specific one for
  conditional compilation.
- Rename the ATHEROS_AR231X config symbol to ATH25.
- Fix include (ar231x_platform.h -> ath25_platform.h).
- Some of AR231x SoCs (e.g. AR2315) have PCI bus support, so remove !PCI
  dependency, which block AHB support build.

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Acked-by: John W. Linville <linville@tuxdriver.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Nick Kossifidis <mickflemm@gmail.com>
Cc: "Luis R. Rodriguez" <mcgrof@do-not-panic.com>
Cc: linux-wireless@vger.kernel.org
Cc: ath5k-devel@lists.ath5k.org
Cc: Linux MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/8248/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

drivers/net/wireless/ath/ath5k/Kconfig

@@ -1,13 +1,13 @@
 config ATH5K
 	tristate "Atheros 5xxx wireless cards support"
-	depends on (PCI || ATHEROS_AR231X) && MAC80211
+	depends on (PCI || ATH25) && MAC80211
 	select ATH_COMMON
 	select MAC80211_LEDS
 	select LEDS_CLASS
 	select NEW_LEDS
 	select AVERAGE
-	select ATH5K_AHB if (ATHEROS_AR231X && !PCI)
-	select ATH5K_PCI if (!ATHEROS_AR231X && PCI)
+	select ATH5K_AHB if ATH25
+	select ATH5K_PCI if !ATH25
 	---help---
 	  This module adds support for wireless adapters based on
 	  Atheros 5xxx chipset.
@@ -54,14 +54,14 @@ config ATH5K_TRACER
 
 config ATH5K_AHB
 	bool "Atheros 5xxx AHB bus support"
-	depends on (ATHEROS_AR231X && !PCI)
+	depends on ATH25
 	---help---
 	  This adds support for WiSoC type chipsets of the 5xxx Atheros
 	  family.
 
 config ATH5K_PCI
 	bool "Atheros 5xxx PCI bus support"
-	depends on (!ATHEROS_AR231X && PCI)
+	depends on (!ATH25 && PCI)
 	---help---
 	  This adds support for PCI type chipsets of the 5xxx Atheros
 	  family.