gamma_spec() coverage

specification Unifloat *gamma_spec( CallContext context, Unifloat *x, IntT *signgam, ErrorCode *errno )

coverages	branches	failures	hits/fails
C	X IS NORMAL POSITIVE		12
	X IS NORMAL NON POSITIVE	failure 26: Requirement failed: {gammaf.lgamma.11} If x is a non-positive integer, either HUGE_VAL or NaN is returned failure 27: Requirement failed: {gamma.lgamma.11} If x is a non-positive integer, either HUGE_VAL or NaN is returned failure 28: Requirement failed: {gammal.lgamma.11} If x is a non-positive integer, either HUGE_VAL or NaN is returned	6/3
	X IS NAN		3
	100% (3/3)		21/3