This patch changes the "acpi_osi=" boot parameter implementation so
that:
1. "acpi_osi=!" can be used to disable all _OSI OS vendor strings by
default. It is meaningless to specify "acpi_osi=!" multiple
times as it can only affect the default state of the target _OSI
strings.
2. "acpi_osi=!*" can be used to remove all _OSI OS vendor strings
and all _OSI feature group strings. It is useful to specify
"acpi_osi=!*" multiple times through kernel command line to
override the current state of the target _OSI strings.
Signed-off-by: Lv Zheng <lv.zheng@intel.com> Reviewed-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Len Brown <len.brown@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>