staging: kpc2000: kpc_i2c: add static qual to local symbols in kpc_i2c.c

kpc_i2c.c declares:
  - two functions
    - pi2c_probe()
    - pi2c_remove()
  - one struct
    - i2c_plat_driver_i
which are local to the file, yet missing the static qualifier. Add the
static qualifier to these symbols.

Signed-off-by: Geordan Neukum <gneukum1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>