USB: gadget: udc: pxa27x_udc: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this.

There is also no need to keep the file dentries around at all, so remove those variables from the device structure.

Cc Daniel Mack <[email protected]>

Cc Haojian Zhuang <[email protected]>

Cc Robert Jarzmik <[email protected]>

Cc Felipe Balbi <[email protected]>

Signed-off-by Greg Kroah-Hartman <[email protected]>