usb: gadged: pch_udc: PCI core handles power state for us

There is no need to repeat the work that is already done in the PCI
driver core. The patch removes excerpts from 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].

While here, convert PM ops to use modern API.

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



Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

[felipe.balbi@linux.intel.com: fixed build break and checkpatch error ]

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>