2 copies of taskcall.c removed

- taskcall.c is 3x in the trunk as part of libc, libsysutil and
  libsys.  It should be only part of libsys.

- only system process should be linked with libsys, therefore using
  raw _taskcall() in service.c is replaced by _syscall()

- the same for minix_rs.c

- lib/other/sys_eniop.c can go without replacement as it is part of
  syslib

lib/sysutil/Makefile.in

@@ -20,7 +20,6 @@ libsys_FILES=" \
 	fkey_ctl.c \
 	tsc_util.c \
 	report.c \
-	taskcall.c \
 	read_tsc.s \
 	read_tsc_64.c \
 	ser_putc.c \