staging: wilc1000: replace drvHandler and hWFIDrv with hif_drv

This patch replaces the variable names of struct host_if_drv used as the
functions' input parameter, drvHandler and hWFIDrv with hif_drv. In
addition, the local variable declared in many functions, pstrWFIDrv is
removed and hif_drv is directly used. A debug message printing pstrWFIDrv is
deleted while removing the local variable because it is not useful as well.
Signed-off-by: Tony Cho <tony.cho@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>