net/wan/fsl_ucc_hdlc: remove set but not used variables 'ut_info' and 'ret'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/net/wan/fsl_ucc_hdlc.c: In function ucc_hdlc_irq_handler:
drivers/net/wan/fsl_ucc_hdlc.c:643:23:
	warning: variable ut_info set but not used [-Wunused-but-set-variable]
drivers/net/wan/fsl_ucc_hdlc.c: In function uhdlc_suspend:
drivers/net/wan/fsl_ucc_hdlc.c:880:23:
	warning: variable ut_info set but not used [-Wunused-but-set-variable]
drivers/net/wan/fsl_ucc_hdlc.c: In function uhdlc_resume:
drivers/net/wan/fsl_ucc_hdlc.c:925:6:
	warning: variable ret set but not used [-Wunused-but-set-variable]

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>