Fix for the following clang build error:
drivers/net/bnx2x/elink.c:10384:41: error: shifting a
negative signed value is undefined [-Werror,-Wshift-negative-value]
vars->eee_status &= ~SHMEM_EEE_1G_ADV <<
~~~~~~~~~~~~~~~~~ ^
Signed-off-by: Harish Patil <harish.patil@qlogic.com>