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: Octeon: Mark expected switch fall-through

Mark switch cases where we are expecting to fall through.

Fix the following warning (Building: cavium_octeon_defconfig mips):

arch/mips/include/asm/octeon/cvmx-sli-defs.h:47:6: warning: this statement
may fall through [-Wimplicit-fallthrough=]

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

MIPS: Octeon: Remove unused SLI types and macros.

Remove all unused bitfields and macros. Convert the remaining
bitfields to use __BITFIELD_FIELD instead of #ifdef.

[ralf@linux-mips.org: Add inclusions of <uapi/asm/bitfield.h> as necessary.]

Signed-off-by: Steven J. Hill <steven.hill@cavium.com>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15405/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: OCTEON: Update register definitions.

Add support for cn68xx, cn61xx, cn63xx, cn66xx and cnf71XX.

Add little-endian register layouts.

Patch cvmx-interrupt-rsl.c for changed definition.

Signed-off-by: David Daney <david.daney@cavium.com>

MIPS: Octeon: Update SOC PCI related register definitions for new chips.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2986/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>