Technically it is the spelling
Malia that is a Hawaiian name.
Maria becomes
Malia in Hawaiian because the Hawaiian language has no sound or letter "r", and the tradition in Hawaii is to change "r's" into "l's" when a name is brought into the Hawaiian language from another language.
You can access information about the original meaning of
Maria and
Mary by clicking on the linked names in this message, which will take you to dictionary entries that are part of this site.