MIPS: ath25: add common parts

Add common code for Atheros AR5312 and Atheros AR2315 SoCs families.

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: Linux MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/8237
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --cc arch/mips/Kbuild.platforms
Simple merge

diff --cc arch/mips/Kconfig
Simple merge

diff --cc arch/mips/ath25/Makefile
Simple merge

diff --cc arch/mips/ath25/Platform
Simple merge

diff --cc arch/mips/ath25/board.c
Simple merge

diff --cc arch/mips/ath25/devices.c
Simple merge

diff --cc arch/mips/ath25/devices.h
Simple merge

diff --cc arch/mips/ath25/prom.c
Simple merge

diff --cc arch/mips/include/asm/mach-ath25/cpu-feature-overrides.h
Simple merge

diff --cc arch/mips/include/asm/mach-ath25/dma-coherence.h
Simple merge

diff --cc arch/mips/include/asm/mach-ath25/gpio.h
Simple merge

diff --cc arch/mips/include/asm/mach-ath25/war.h
Simple merge