ACPI: replace kmalloc+memset with kzalloc

arch/ia64/kernel/cpufreq/acpi-cpufreq.c

drivers/acpi/ac.c

drivers/acpi/acpi_memhotplug.c

drivers/acpi/asus_acpi.c

drivers/acpi/battery.c

drivers/acpi/container.c

drivers/acpi/ec.c

drivers/acpi/fan.c

drivers/acpi/i2c_ec.c

drivers/acpi/ibm_acpi.c

drivers/acpi/pci_bind.c

drivers/acpi/pci_irq.c

drivers/acpi/pci_link.c

drivers/acpi/pci_root.c

drivers/acpi/power.c

drivers/acpi/processor_core.c

drivers/acpi/sbs.c

drivers/acpi/scan.c

drivers/acpi/thermal.c

drivers/acpi/utils.c