Alchemy: make OSS I2S driver build

Hello.

Alchemy OSS I2S driver (sound/oss/au1550_i2s.c) doesn't build if I2C
driver (drivers/i2c/busses/i2c_au1550.c) is not enabled because pb1550_wm_codec_write() is defined there (a dirty hack). So, mark that dependency in drivers/i2c/busses/Kconfig.

WBR, Sergei

PS: Also, I've noticed that both I2S and I2C drivers depend solely on SOC_AU1550. Shouldn't they also work on Au1200?

index b7bd8ab..07eb4a7 100644
@@ -242,6 +242,9 @@ config SOUND_AU1550_AC97
 config SOUND_AU1550_I2S
 	tristate "Au1550 I2S Sound"
 	depends on SOUND_PRIME && SOC_AU1550
+	# Weird I2S driver needs I2C driver to talk to the codec...
+	select I2C
+	select I2C_AU1550
 
 config SOUND_TRIDENT
 	tristate "Trident 4DWave DX/NX, SiS 7018 or ALi 5451 PCI Audio Core"