ACPI: processor: Check for null return of devm_kzalloc() in fch_misc_setup()

In the Linux kernel, the following vulnerability has been resolved: ACPI: processor: Check for null return of devm_kzalloc() in fch_misc_setup() devm_kzalloc() may fail, clk_data->name might be NULL and will cause a NULL pointer dereference later. [ rjw: Subject and changelog edits ]