advfs: add typedef for vm_map_t
advfs: Add parentheses around assigments in if()
advfs: Add prototypes for bs_fragbf_thread and frag_group_dealloc
advfs: Enhance const correctness of PrintAction adn UnpinAction
advfs: Add semicolon after KASSERT()
advfs: Remove unused variables
advfs: Remove /* from a body of comment
advfs: Remove empty macro
advfs: Initial work on the way to go for native UVM
advfs: Minor scratch update