MIPS: Use fallthrough for arch/mips

Convert the various /* fallthrough */ comments to the pseudo-keyword
fallthrough;

Done via script:
https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe@perches.com/

Signed-off-by: Liangliang Huang <huangll@lemote.com>
Reviewed-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: fix some more fall through errors in arch/mips

Fix these errors:

arch/mips/cavium-octeon/executive/cvmx-pko.c:489:7: error: this statement may fall through [-Werror=implicit-fallthrough=]
arch/mips/bcm63xx/dev-flash.c:89:3: error: this statement may fall through [-Werror=implicit-fallthrough=]
arch/mips/ath79/setup.c:155:17: error: this statement may fall through [-Werror=implicit-fallthrough=]
arch/mips/ar7/setup.c:50:3: error: this statement may fall through [-Werror=implicit-fallthrough=]

Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Crispin <john@phrozen.org>
Cc: Matthias Schiffer <mschiffer@universe-factory.net>
Cc: "Petr Štetiar" <ynezz@true.cz>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Burton <paul.burton@mips.com>

MIPS: BCM63XX: add support for BCM3368 Cable Modem

The Broadcom BCM3368 Cable Modem SoC is extremely similar to the
existing BCM63xx DSL SoCs, in particular BCM6358, therefore little effort
in the existing code base is required to get it supported. This patch adds
support for the following on-chip peripherals:

- two UARTS
- GPIO
- Ethernet
- SPI
- PCI
- NOR Flash

The most noticeable difference with 3368 is that it has its peripheral
register at 0xfff8_0000 we check that separately in ioremap.h. Since
3368 is identical to 6358 for its clock and reset bits, we use them
verbatim.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: cernekee@gmail.com
Cc: jogo@openwrt.org
Patchwork: https://patchwork.linux-mips.org/patch/5499/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: BCM63XX: add flash detection for BCM6362

BCM6362 support booting from SPI flash and NAND.

Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/5012/
Acked-by: John Crispin <blogic@openwrt.org>

MIPS: BCM63XX: Add basic BCM6328 support

This includes CPU speed, memory size detection and working UART, but
lacking the appropriate drivers, no support for attached flash.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: Maxime Bizon <mbizon@freebox.fr>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Kevin Cernekee <cernekee@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/3951/
Reviewed-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: BCM63XX: Add flash type detection

On BCM6358 and BCM6368 the attached flash type is exposed through a
bootstrapping register. Use it for auto detecting the flash type on
those and default to parallel flash for earlier SoCs.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: Maxime Bizon <mbizon@freebox.fr>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Kevin Cernekee <cernekee@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/3954/
Reviewed-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: BCM63XX: Move flash registration out of board_bcm963xx.c

board_bcm963xx.c is already large enough.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: Maxime Bizon <mbizon@freebox.fr>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Kevin Cernekee <cernekee@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/3952/
Reviewed-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>