um: trim kern.h

most of the functions in there are not used in anything that ends up
including that header...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

arch/um/include/shared/kern.h

@@ -13,28 +13,10 @@
  * includes.
  */
 
-extern int errno;
-
-extern int clone(int (*proc)(void *), void *sp, int flags, void *data);
-extern int sleep(int);
 extern int printf(const char *fmt, ...);
-extern char *strerror(int errnum);
-extern char *ptsname(int __fd);
-extern int munmap(void *, int);
 extern void *sbrk(int increment);
-extern void *malloc(int size);
-extern void perror(char *err);
-extern int kill(int pid, int sig);
-extern int getuid(void);
-extern int getgid(void);
 extern int pause(void);
-extern int write(int, const void *, int);
 extern void exit(int);
-extern int close(int);
-extern int read(unsigned int, char *, int);
-extern int pipe(int *);
-extern int sched_yield(void);
-extern int ptrace(int op, int pid, long addr, long data);
 
 #endif