acpi: add checking for NULL early param

The early_param handling function could recieve NULL pointer as argument
in case if user didn't enter parameter value.  So we have to be ready for
a such situation and do check for NULL pointer if needed.

Signed-off-by: Cyrill Gorcunov <[email protected]>
Cc: Andi Kleen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Andi Kleen <[email protected]>
1 file changed