New profile protocol

- when kernel profiles a process for the first time it saves an entry
  describing the process [endpoint|name]

- every profile sample is only [endpoint|pc]

- profile utility creates a table of endpoint <-> name relations and
  translates endpoints of samples into names and writing out the
  results to comply with the processing tools

- "task" endpoints like KERNEL are negative thus we must cast it to
  unsigned when hashing

kernel/proc.h

@@ -241,6 +241,7 @@ struct proc {
 					 * regs are significant (initialized)*/
 #define MF_SENDING_FROM_KERNEL	0x2000 /* message of this process is from kernel */
 #define MF_CONTEXT_SET	0x4000 /* don't touch context */
+#define MF_SPROF_SEEN	0x8000 /* profiling has seen this process */
 
 /* Magic process table addresses. */
 #define BEG_PROC_ADDR (&proc[0])