hppa: Cleanup libm-test-ulps.

Joseph Myers noted that there were several old and really very
incorrect values in the hppa libm-test-ulps. This patch removes
all of the ulps values for ceil, floor, rint, round, trun,
llrint, and llround, all of which were previously incorreclty
added (including some negative values which are really wrong).

---
ports/

2013-05-15  Carlos O'Donell  <carlos@redhat.com>

	* sysdeps/hppa/fpu/libm-test-ulps: Remove old values for ceil, floor,
	rint, round, trunc, llrint, and llround.
Remove const attribute on get_log2

This function is not const, as it can modify log2_m and log2_m_inited.