misc: pch_phub: Remove superfluous descriptions to non-existent args 'offset_address'

misc: pch_phub: Remove superfluous descriptions to non-existent args 'offset_address'

Probably a copy 'n' paste error, 'offset_address' has never been
part of the pch_phub_{read,write}_gbe_mac_addr() functions.

Squashes the following W=1 warnings:

 drivers/misc/pch_phub.c:450: warning: Excess function parameter 'offset_address' description in 'pch_phub_read_gbe_mac_addr'
 drivers/misc/pch_phub.c:462: warning: Excess function parameter 'offset_address' description in 'pch_phub_write_gbe_mac_addr'

Cc: Masayuki Ohtak <masa-korg@dsn.okisemi.com>
Cc: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20200701085853.164358-15-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>