mfd: Don't use I2C-specific suspend and resume operations for tps65090

The legacy suspend operations have been deprecated and printing warnings
on boot for over a year now.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Venu Byravarasu <vbyravarasu@nvidia.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>