The l13a rail on trogdor devices has always been intended to be
always-on on both S0 and S3. Different trogdor variants use l13a in
slightly different ways, but the overall theme is that it's a 1.8V
rail that the board uses for things that it wants powered in on S0 and
S3. On many boards this includes the boot SPI (AKA qspi).

For all intents and purposes this patch is actually a no-op since
something else in the system seems to already be keeping the rail on
all the time (confirmed via multimeter). That "something else" was
postulated to be the modem but the rail is on / stays on even without
the modem/wifi coming up so it's likely the boot config. In any case,
making the fact that this is always-on explicit seems like a good
idea.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230323102605.4.I9f47a8a53eacff6229711a827993792ceeb36971@changeid