regulator: tps65917/palmas: Add bypass "On" value

When commit b554e1450658 ("regulator: tps65917/palmas: Add bypass
ops for LDOs with bypass capability") introduced bypass capability
to palmas regulator, it went with the assumption that regulator
regmap helpers just check val against the bypass_mask.

Unfortunately, this ignored the explicit "on" and "off" values when
the register value is masked with bypass_mask in commit ca5d1b3524b4
("regulator: helpers: Modify helpers enabling multi-bit control").

With the recent commit dd1a571daee7 ("regulator: helpers: Ensure
bypass register field matches ON value"), this issue gets highlighted
and fails tps65917/palmas based platforms which need regulators/ldos
that have bypass capability.

Introduce the bypass_on value appropriately for tps65917/palmas
regulator.

Fixes: b554e1450658 ("regulator: tps65917/palmas: Add bypass ops for LDOs with bypass capability")
Cc: Keerthy <j-keerthy@ti.com>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>