Remove doubly linked list of `Platform_Memory_Block` fields

core/mem/virtual/virtual.odin

@@ -96,13 +96,6 @@ memory_block_alloc :: proc(committed, reserved: uint, flags: Memory_Block_Flags)
 	pmblock.block.committed = committed
 	pmblock.block.reserved  = reserved
 
-	sentinel := &global_platform_memory_block_sentinel
-	platform_mutex_lock()
-	pmblock.next = sentinel
-	pmblock.prev = sentinel.prev
-	pmblock.prev.next = pmblock
-	pmblock.next.prev = pmblock
-	platform_mutex_unlock()
 	
 	return &pmblock.block, nil
 }
@@ -157,11 +150,6 @@ alloc_from_memory_block :: proc(block: ^Memory_Block, min_size, alignment: uint)
 
 memory_block_dealloc :: proc(block_to_free: ^Memory_Block) {
 	if block := (^Platform_Memory_Block)(block_to_free); block != nil {
-		platform_mutex_lock()
-		block.prev.next = block.next
-		block.next.prev = block.prev
-		platform_mutex_unlock()
-		
 		platform_memory_free(block)
 	}
 }

core/mem/virtual/virtual_platform.odin

@@ -1,13 +1,10 @@
 //+private
 package mem_virtual
 
-import "core:sync"
-
 Platform_Memory_Block :: struct {
 	block:      Memory_Block,
 	committed:  uint,
 	reserved:   uint,
-	prev, next: ^Platform_Memory_Block,
 } 
 
 platform_memory_alloc :: proc "contextless" (to_commit, to_reserve: uint) -> (block: ^Platform_Memory_Block, err: Allocator_Error) {
@@ -33,28 +30,6 @@ platform_memory_free :: proc "contextless" (block: ^Platform_Memory_Block) {
 	}
 }
 
-platform_mutex_lock :: proc() {
-	sync.mutex_lock(&global_memory_block_mutex)
-}
-
-platform_mutex_unlock :: proc() {
-	sync.mutex_unlock(&global_memory_block_mutex)
-}
-
-global_memory_block_mutex: sync.Mutex
-global_platform_memory_block_sentinel: Platform_Memory_Block
-global_platform_memory_block_sentinel_set: bool
-
-@(init)
-platform_memory_init :: proc() {
-	if !global_platform_memory_block_sentinel_set {
-		_platform_memory_init()
-		global_platform_memory_block_sentinel.prev = &global_platform_memory_block_sentinel
-		global_platform_memory_block_sentinel.next = &global_platform_memory_block_sentinel
-		global_platform_memory_block_sentinel_set = true
-	}
-}
-
 platform_memory_commit :: proc "contextless" (block: ^Platform_Memory_Block, to_commit: uint) -> (err: Allocator_Error) {
 	if to_commit < block.committed {
 		return nil