Remove very old libm-test-ulps entries.

I noticed that some libm-test-ulps files still had long-obsolete
entries for *_tonearest functions, which will no longer be used since
functions with FE_TONEAREST explicitly set aren't tested separately
from those functions with it as the default rounding mode any more.

This patch removes those obsolete entries.  However, as they are a
sign of libm-test-ulps not having been regenerated from scratch for a
long time, I strongly advise people testing on those platforms to
remove / truncate the libm-test-ulps file, run "make regen-ulps" and
commit the regenerated-from-scratch file.  (Ideally any failures of
libm tests still present after regeneration would be investigated /
fixed - there are several open "math" bugs spread across these
platforms - but simply regenerating from scratch improves things.)

	* sysdeps/hppa/fpu/libm-test-ulps: Remove *_tonearest entries.
	* sysdeps/ia64/fpu/libm-test-ulps: Likewise.
	* sysdeps/m68k/m680x0/fpu/libm-test-ulps: Likewise.
	* sysdeps/microblaze/libm-test-ulps: Likewise.
	* sysdeps/sh/libm-test-ulps: Likewise.