i2c: ismt: PCI core handles power state for us

i2c: ismt: PCI core handles power state for us

There is no need to repeat the work that is already done in the PCI driver
core. Remove suspend and resume callbacks.

Note that there is no more calls performed to enable or disable a PCI
device during suspend-resume cycle. Nowadays they seems to be
superfluous. Someone can read more in [1].

[1] https://www.kernel.org/doc/ols/2009/ols2009-pages-319-330.pdf

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>