Fix type.
 [jmk] --rw-rw-r-- M 905070 glenda sys 2531 Dec  7 19:50 sys/src/ape/lib/ap/plan9/profile.c
	/n/sourcesdump/2005/1207/plan9/sys/src/ape/lib/ap/plan9/profile.c:9,15 - 
	/n/sourcesdump/2005/1208/plan9/sys/src/ape/lib/ap/plan9/profile.c:9,15
	  extern	long*	_clock;
	  extern	long	_callpc(void**);
	  extern	long	_savearg(void);
	- extern	void*	sbrk(int);
	+ extern	void*	sbrk(unsigned long);
	  
	  typedef unsigned long ulong;