ACPICA: Update comments for ACPICA name - no functional change.

Change all comments that contain the string "ACPI CA" to "ACPICA"
so that the name is standard across the entire source base.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>