remoteproc: qcom: qcom_q6v5_adsp: Fix some return value check
In case of error, the functions devm_kcalloc() and devm_ioremap()
returns NULL pointer not ERR_PTR(). The IS_ERR() test in the return
value check should be replaced with NULL test.
Also removed -EPROBE_DEFER check since devm_kcalloc never return
this error.