Bug 31764

	The gamma(3) man page states that gamma(x) is gamma(x), whilst
	lgamma(x) returns ln(gamma(x)).  gamma(x) actually returns
	the log of gamma(x).

Fix: 

The standard seems to be that gamma() actually return log gamma(),
	therefore the implementation is correct, it's just the man page
	that is wrong.  That said, there are two implementations of gamma
	provided: src/lib/libm/common_source/gamma.c appears to match the
	man page, whilst src/lib/msun/src/w_gamma.c is the one in libm.
How-To-Repeat: #include <math.h>
#include <stdio.h>

int main()
{
    double d;

    for (d = 1; d < 10; d++) {
	printf("gamma(%f) = %f\n", d, gamma(d));
    }
}

	If the man page was correct, this program would return:
gamma(1.000000) = 1.000000
gamma(2.000000) = 1.000000
gamma(3.000000) = 2.000000
gamma(4.000000) = 6.000000
gamma(5.000000) = 24.000000
gamma(6.000000) = 120.000000
gamma(7.000000) = 720.000000
gamma(8.000000) = 40320.000000
gamma(9.000000) = 362880.000000

	It actually returns:
gamma(1.000000) = 0.000000
gamma(2.000000) = 0.000000
gamma(3.000000) = 0.693147
gamma(4.000000) = 1.791759
gamma(5.000000) = 3.178054
gamma(6.000000) = 4.787492
gamma(7.000000) = 6.579251
gamma(8.000000) = 8.525161
gamma(9.000000) = 10.604603