update atheros 2.6 port - add support for the older chip generation

target/linux/atheros-2.6/config

target/linux/atheros-2.6/config-diff

target/linux/atheros-2.6/files/arch/mips/atheros/Kconfig

target/linux/atheros-2.6/files/arch/mips/atheros/Makefile

target/linux/atheros-2.6/files/arch/mips/atheros/ar5312.c

target/linux/atheros-2.6/files/arch/mips/atheros/ar5312.h

target/linux/atheros-2.6/files/arch/mips/atheros/ar5315.c

target/linux/atheros-2.6/files/arch/mips/atheros/ar5315.h

target/linux/atheros-2.6/files/arch/mips/atheros/ar531x.h

target/linux/atheros-2.6/files/arch/mips/atheros/board.c

target/linux/atheros-2.6/files/arch/mips/atheros/irq.c

target/linux/atheros-2.6/files/arch/mips/atheros/prom.c

...et/linux/atheros-2.6/files/drivers/mtd/devices/spiflash.c

...et/linux/atheros-2.6/files/drivers/mtd/devices/spiflash.h

target/linux/atheros-2.6/files/drivers/net/ar2313/Makefile

target/linux/atheros-2.6/files/drivers/net/ar2313/ar2313.c

target/linux/atheros-2.6/files/drivers/net/ar2313/ar2313.h

...t/linux/atheros-2.6/files/drivers/net/ar2313/ar2313_msg.h

target/linux/atheros-2.6/files/drivers/net/ar2313/dma.h

target/linux/atheros-2.6/files/drivers/net/ar2313/platform.h