i2c: qup: Fix error return code in qup_i2c_bam_schedule_desc()

Fix to return the error code from qup_i2c_change_state()
instaed of 0 in qup_i2c_bam_schedule_desc().

Fixes: fbf9921f ("i2c: qup: Fix error handling")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>