riscv: dts: sifive unleashed: Add PWM controlled LEDs

stable inclusion
from stable-v5.10.157
commit 1c9eb641d13e8dd8c301ead9c395dcc1104c419d
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7MU59

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1c9eb641d13e8dd8c301ead9c395dcc1104c419d



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[ Upstream commit 8bc8824d ]

This adds the 4 PWM controlled green LEDs to the HiFive Unleashed device
tree. The schematic doesn't specify any special function for the LEDs,
so they're added here without any default triggers and named d1, d2, d3
and d4 just like in the schematic.

Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20221012110928.352910-1-emil.renner.berthing@canonical.com


Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>