Fix issues in long and double testing.

This does not enable the tests (something for later).
This CL also enables the tests for half_recip.

	modified:   gen_runtime.cpp
	modified:   rs_core_math.spec
	modified:   ../scriptc/rs_core_math.rsh

Change-Id: If8ef104ab05edfef160a3530283480fd2cd92f3b
3 files changed