Staging: vt6656: Fix Sparse Warning: cast from restricted gfp_t in hostap.c

This patch fixes the following type of sparse warnings:

drivers/staging/vt6656/hostap.c:688:42: warning: cast from restricted gfp_t
drivers/staging/vt6656/hostap.c:688:42: warning: incorrect type in argument 2 (different base types)
drivers/staging/vt6656/hostap.c:688:42: expected restricted gfp_t [usertype] flags
drivers/staging/vt6656/hostap.c:688:42: got int [signed] <noident>

Signed-off-by: Ebru Akagunduz <ebru.akagunduz@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>