Cleanup: fix misleading comment

LinearAllocator does not REallocate, it just allocates a new buffer.

source/blender/blenlib/BLI_linear_allocator.hh

@@ -7,7 +7,7 @@
  *
  * A linear allocator is the simplest form of an allocator. It never reuses any memory, and
  * therefore does not need a deallocation method. It simply hands out consecutive buffers of
- * memory. When the current buffer is full, it reallocates a new larger buffer and continues.
+ * memory. When the current buffer is full, it allocates a new larger buffer and continues.
  */
 
 #pragma once